Virtual Audio Cable 4 Release History

Version 4.70 (17.04.2023.)
  • Added ARM64 binaries.
  • Fixed a driver bug that caused render streams to speed up when volume control and/or format conversion are used.
  • Fixed a driver bug that caused OF/UF values in the stream termination event to always be zero.
  • Added client clock adjustment feature to the driver, allowing applications to adjust cable clock on the fly, without changing cable clock correction value permanently.
  • Packet mode support is disabled by default to improve stream reliability in typical applications. Packet mode controls added to VAC Control Panel.
  • Added a workaround for Windows bug that requires to start high-level clients before KS ones.
  • Added the name of the process that created the stream to the stream information.
  • Changed algorithm of actual sampling rate calculation for better reflection of recent changes.
  • Added a dynamic cable clock adjustment to Audio Repeater applications.
  • Changed layout of Audio Repeater KS window to fit low-height screens.
  • Audio Repeater MME now finds the endpoint by name when the transfer is started. It allows to avoid restarting the app if endpoint order was changed (when audio devices are plugged/unplugged, default endpoint is changed etc.).
  • Added workaround to Setup application to remove hidden "phantom" device instance if the previous installation was forcibly aborted.
  • Setup application now searches for uninstallers of older versions.
  • VAC driver API version increased to 6.
Version 4.65 (30.01.2021.)
  • Fixed a bug introduced in 4.64: KS RT Audio filters didn't expose event driven mode (notification) support, so Windows Audio Engine didn't use short audio buffers.
  • Fixed a bug with output top channels confusion on Audio Repeater KS.
  • Signal level indicators now display visible levels for any non-silent signal, including a very low noise.
  • Double-click on a cable row acts like the "Cable Info" button.
  • Some format/attribute errors are now shown in the event log.
  • Added format attribute support policies as a workaround for some Windows bugs.
  • Stream management code in Audio Repeater MME is rewritten to decrease latency.
  • Added the ability to use comments in Audio Repeater configuration files.
  • Changed queue management algorithm in both MME and KS versions of Audio Repeater.
Version 4.64 (21.07.2020.)
  • Fixed the installer that didn't enable the device in XP.
  • Fixed a minor bug in timer event handling.
  • Changed system timer resolution handling algorithm for better stability.
  • Some improvements in Audio Repeater KS.
Version 4.62 (04.01.2020.)
  • Fixed driver signature issues in Win7/8/8.1.
  • Fixed minor bugs in Setup application.
Version 4.61 (02.01.2020.)
  • Fixed Audio Repeater bug that caused hangup on device disconnection.
  • Added top speaker channel support.
  • Added signal processing mode support.
  • Replaced independent cable clock sources with a single kernel timer to allow multiple cables to be coherent.
  • Fixed a bug in calculation of minimal cable event period (Cable Info window).
  • Fixed a bug in WaveRT capture stream processing that caused data loss on short buffering time.
  • Increased cable clock calculation precision, eliminating error accumulation.
  • Increased clock register bitness up to 64 and precision up to QPC resolution.
  • Added workaround for audio device properties confusion due to permanent property caching in Win10.
  • Cumulative algorithm for actual sampling rate calculation.
  • Added Sound Settings and Microphone Privacy buttons to the Control Panel.
  • Added Microphone Privacy reminders to Audio Repeater and Control Panel.
  • Changed signal level indicators from linear to logarithmic for better visibility.
  • Added gauge coloring to Audio Repeater windows.
  • Added automatic uninstaller launching feature to the setup application.
  • Added default endpoint checking feature to the setup application.
  • In the setup application, using more reliable device uninstallation algorithm.
  • Clarified names of System Audio Engine and Audio Service.
  • Added feature-limited free version.
  • Removed three-cable limitation from trial version.
Version 4.60 (16.11.2018.)
  • Added RT Audio packet streaming support.
  • Increased maximum number of supported channels to 32 (may cause problems, consult the manual).
  • Decreased default timer event period down to 3 ms to avoid RT Audio (WaveRT) glitches.
  • Show actual and potential cable/stream problems with state icons.
  • Show circular buffer duration and amount of buffered data (in milliseconds) in stream lists.
  • Show stream processing modes in stream lists.
  • Made application windows DPI aware (no blurring on high DPI displays).
  • Added high-resolution icons.
  • Added tooltips to application controls.
  • Added "Help" button to Audio Repeater applications.
  • Added a private property set accessible via any KS interface.
  • Added registry parameter for timer resolution adjustment.
  • Increased trial voice reminder delay to 30 minutes.
  • Added voice reminder status (silent/audible) indication to Control Panel.
  • Removed stream data buffer and stream watermark support because they were hard to tune and not very efficient against stream stability problems.
  • Some changes in Conrol API, not binary compatible with previous versions.
  • Fixed bug causing BSOD on some rare formats and settings combinations.
  • Fixed buffer notification positions.
  • Fixed minor bugs.
Version 4.51 (08.07.2018.)
  • Added second INF file to install under Win 6.x (Vista, Win 7/8/8.1).
  • Changed class/interface GUIDs for the driver, Control API and Native Mode key (custom versions only).
  • Decreased noise level in Native Mode.
  • Uninstall entry is now created with a constant product GUID.
  • Minor bugfixes.
Version 4.50 (01.10.2018)
  • Fixed a bug caused Control Panel crash if VAC driver cannot be restarted.
  • Split monolithic cable KS filter into two separate render/capture filters.
  • Added WaveRT (RTAudio) and WaveCyclic port/miniport interface support.
  • Removed 16-cable limitation from the default INF file.
  • Met Device Guard requirements.
  • Signed with EV certificate to allow loading by Win10 in Secure Boot mode.
  • Added load/save configuration features to Audio Repeater.
  • Added actual sampling rate display to Audio Repeater.
  • Added stream's actual sampling rate and run time display to VAC Control Panel.
  • API: replaced CreationTime field in CableInfo with LifeTime to prevent calculation errors.
Version 4.15 (04.01.2016)
  • Replaced source line summer with a multiplexer.
  • Added recording side volume control.
  • Added cable information window with stream information list.
  • Added event log feature.
  • Fixed some bugs in KS version of Audio Repeater.
  • Added some options and useful information display to KS version of Audio Repeater.
  • Added MMCSS task registration to Audio Repeater to control thread priority.
  • Fixed a bug in resuming the streaming after sleep/hibernation.
  • Added Ctrl-C support in Audio Repeater "Wave in" and "Wave out" fields to copy device name to the clipboard.
  • Increased small buffer movement uniformity between VAC driver and applications.
Version 4.14 (10.06.2014)
  • Fixed a bug caused playback at higher speed.
  • Added a workaround for PortCls bug (GetMaxMapRegisters function) causing position freezing.
  • Fixed a bug caused signal level to be painted over the header in Control Panel application.
  • Added stream buffer control to minimize overflows/underflows.
  • Added button to restart System Audio Engine.
  • Now filter volume/mute nodes always report 8-channel support.
Version 4.13 (08.03.2013)
  • Fixed a bug preventing stream buffer watermark parameters from being loaded on restart.
  • Fixed bugs causing integer divide overflows in Audio Repeater (both MME and KS versions).
  • Added a workaround for PortCls bug causing BSOD (bugchecks 0x50 or 0xD6) in GetMaxMapRegisters function if Driver Verifier with the special pool is used for VAC driver verification.
  • Added peak signal level indicators to Control Panel.
  • Changed signal level indication in Audio Repeater from average to peak.
  • Fixed stream position timestamp error if PortCls is not used (occurred in Open Broadcaster Software).
  • Added a feature to control playback pin type (speaker or line out).
  • Fixed sleep/hibernate problems.
  • Added master volume control.
Version 4.12 (04.01.2012)
  • Fixed RtAudio buffer processing bug in Audio Repeater KS.
  • Added clock rate display to Audio Repeater.
  • Changed number of worker threads limit to a number of logical CPUs.
Version 4.11 (03.14.2012)
  • Added cable multi-selection feature to Control Panel.
  • Clock correction precision increased to 0.0000001% (1E-8%).
  • Added volume boost feature.
  • Fixed sampling rate change bug caused incorrect playback speed.
  • Rewritten data processing code from DPC to system thread set to minimize interlocked waiting and improve performance on multi-CPU/core systems.
  • Added stream buffer watermark control feature to improve stream stability.
  • Added "Reset counters" buttons (Control Panel) to reset cable/driver counters.
  • Minimum possible sampling rate increased from 200 to 1000.
  • Fixed a bug in KS Audio Repeater (device name string length was limited to 31 chars as in MME version).
  • Optimized KS Audio Repeater algorithms for more reliable transfer.
  • Added a feature to Audio Repeater: now command-line options can specify device number instead of its name to avoid name collisions if several adapters of the same type coexists.
  • Added several channel mixing/distribution schemes.
  • Added channel scatter/gather mode and cable channel mixing control.
  • Increased clock correction precision (registry value format is changed).
  • Added a privilege elevation manifest to Setup application to elevate privileges automatically.
  • Maximum sampling rate changed from 1000000 to 384000 in accordance with MS requirements.
  • Add "already installed" warning to Setup application.
  • Fixed some node property errors.
  • Fixed some minor bugs.
Version 4.10 (02.15.2010)
  • Added IPrefetchOffset interface support (more stable audio in XP/Vista/Server 2008/Win7).
  • Added a workaround to avoid Skype freezing and to stabilize streaming in heavy load cases.
  • Changed voice reminder policy in trial version.
  • Added tray icon support to Audio Repeater.
  • Added Kernel Streaming version of Audio Repeater.
  • Added Wikipedia references in the user manual.
  • Fixed some bugs in volume control code.
  • Fixed a bug caused timer resolution restoration when a last cable stream was closed.
  • Added timer resolution correction on return from standby.
  • Added load splitting among CPUs/cores.
  • Added Authenticode digital signature from NTONYX.
  • Added instance closing feature to Audio Repeater.
Version 4.09 (06.27.2008)
  • Fixed a bug caused system crash in case of incorrect volume settings.
  • Now multichannel nodes are exposed correctly (individual sliders instead of the Pan slider).
  • Fixed a bug caused break instruction crash (0x80000003) on a floating point format query.
  • Fixed a bug caused system crash in low memory situation.
  • Added a test signature to 64-bit driver module.
  • Increased average time interval between voice reminders in trial version.
  • Increased clock correction precision in Control Panel to 1/1000th of a percent.
Version 4.08 (09.14.2007)
  • Clock correction amount is now represented and specified in percent values.
  • Changed clock correction algorithm to increase sampling rate precision.
  • Fixed a bug in the INF file that prevented Virtual Cables from being used via KS Proxy (for example, as a DirectShow WDM filter).
  • Fixed a bug in format checking code that limited number of channels to 2 under Vista.
Version 4.07 (06.28.2007)
  • Removed another debug break instruction caused a bugcheck in rare cases.
Version 4.06 (05.15.2007)
  • Fixed installer bug caused the driver to stay disabled after installation.
  • Removed a debug break instruction caused a bugcheck in rare cases.
Version 4.05 (05.12.2007)
  • Added a clock correction feature.
  • Added configuration options for source line set (affects endpoint creation in Vista).
  • Changed service name in INF file to eliminate conflicts with VAC3.
  • Added more correct multi-channel support under Vista.
  • Added a workaround for Vista portcls.sys bug (a miniport stream can be destructed without been stopped).
  • Removed the "Mic" source line (capture endpoint in Vista) from the default source line set.
  • Changed "Milliseconds per interrupt" default value to 7 to improve DirectSound stability.
  • Improved stream stability on short buffering times.
  • Changed the Control Panel interface.
Version 4.04 (12.31.2006)
  • Fixed a bug in topology description (fake recording controls were not accessible).
  • Fixed some synchronization bugs (the system hangs while several cables are heavily used).
  • Added a pitch (frequency) shifting support.
  • Added a limited Vista support.
Version 4.03 (07.31.2006)
  • Fixed a bug that caused change of signal pitch. This issue was previously considered as DirectSound bug and was described in FAQ section related to speech engines. This section has been removed from the FAQ.
Version 4.02 (05.22.2006)
  • Added 64-bit binaries.
  • Some minor corrections.
Version 4.01 (03.24.2006)
  • Fixed some bugs.
  • Changed default stream format limiting type to the "Cable range".
Version 4.00 (03.06.2006)
  • First public release