Version 1.0.0.79 · stable
CustomA2DP replaces the stock btha2dp stack with its own implementation
in the kernel: its own SBC codec and its own AVDTP transport over L2CAP.
We worked to raise sound quality, make headset switching instant, and keep
operation stable.
Why
The SBC bitpool is locked to a single value — quality is whatever the stack decided.
Features
Not a wrapper around someone else's stack: a self-contained audio path. The WaveRT miniport, topology, AVDTP transport and the SBC codec live in one .sys and talk to the Bluetooth radio directly.
Codec and AVDTP transport run inside the driver. No dependency on
BluetoothUserService, so the stream never dies just because that
service got busy.
Signaling and media channels stay open through idle time, so the headset is always ready and playback starts without another AVDTP handshake.
A DSP equalizer with a headroom limiter: you can push the bass without harsh clipping. The curve applies to the running stream without a restart.
In auto mode the target follows the render sink. Switch the device in
the tray and the stream moves to the other headset — no silence, no stale phantom
endpoints.
Before tearing the stream down the driver catches up with silence in short SBC packets, so the DAC never clicks at the boundary.
Stream status, an L2CAP/AVDTP/SBC log and device start records land in
%ProgramData%\CustomA2DP. Every byte of the AVDTP exchange is visible
with timestamps.
SBC bitpool, idle timeout and warm connect are set from the configurator. The bitpool sets the bitrate: 345 → 512+ is ~53 → ~99 kbit/s, and the stock stack keeps it fixed.
The uninstaller hands A2DP nodes back to the stock driver and cleans DriverStore. HFP, AVRCP and COM ports keep running on Microsoft drivers the whole time.
How it works
Sound from any application goes through the standard WASAPI interface, so every player, browser, game and streaming service works without reconfiguration.
Configurator
A native application with no .NET runtime. It picks the active A2DP endpoint, makes it default for console and multimedia, warms the channel with a real WASAPI stream, and can power-cycle the radio to force a reconnection.
Requirements
The driver carries a test certificate, so Secure Boot must be disabled. The installer takes care of it and asks for a single reboot.
Install
A single CustomA2DP-Install.exe file. There is nothing to unpack by hand.
Approve the UAC prompt. The installer deploys the files, trusts both certificates, enables test signing and installs the package via pnputil.
A "reboot required" message is expected. Do not run the installer again: the driver loads on its own.
The headset A2DP node should move to CustomA2DP. If it does not: Device Manager → Bluetooth → Update driver → Browse → %ProgramFiles%\CustomA2DP\package\customa2dp.inf.
Open "CustomA2DP Config" from the Start menu, pick the device, enable the EQ and verify with check.cmd.
FAQ
Yes, it is mandatory. The driver is signed with a test certificate rather than a Microsoft one, so an active Secure Boot will refuse to load it. The installer turns on test signing with bcdedit /set testsigning on and asks for one reboot. There is no way around this: the boot loader will not load the package while Secure Boot is enforced. This is a temporary state — see support for what donations change.
No. Only A2DP nodes are re-bound (MEDIA class, 0000110B). Hands-Free, AVRCP and COM port nodes keep running on the stock Microsoft drivers, so the headset microphone and playback controls stay intact.
Run uninstall.cmd from %ProgramFiles%\CustomA2DP, or remove the app through Settings → Apps. The uninstaller drops the packages from DriverStore and removes the certificates, shortcuts and program folder. Test signing stays on and can be disabled manually with bcdedit /set testsigning off plus a reboot.
Soundcore Life Q30, JBL Flip 7 and D300-DH. The driver implements the standard A2DP profile with the SBC codec, so it works with any A2DP headset. Exotic codecs such as LDAC and aptX are not supported — they need a different stack, not a tweak to this driver.
Almost always the Bluetooth radio fails to bring up a new ACL link to the new headset: Windows still believes the device is connected until you physically switch it or power-cycle the radio. The configurator can do that power-cycle for you — that is what the "Reconnect" button does.
The driver constantly writes to %ProgramData%\CustomA2DP: customa2dp_status.txt (state, bitpool, frames sent, errors), customa2dp_bt.log (detailed L2CAP, AVDTP and SBC pump log) and customa2dp_start.log (device start and stop). For a quick check, run check.cmd.
The driver is free, with no accounts, telemetry or subscription. Donations are optional: they cover signing the packages and test hardware, and partially go to supporting the project assistant.
Three things: 1) in Device Manager the A2DP node shows CustomA2DP, not Microsoft; 2) the configurator has the right endpoint selected and set as default for both console and multimedia; 3) customa2dp_bt.log contains the line audio stream established, which proves the SBC pump started. If that line is missing, the problem is the driver binding, not encoding.
Download
One self-extracting installer with the driver, the configurator, the certificates and the check utilities. No system files are overwritten: only the A2DP nodes and the driver store are touched.
Downloads —
Support
CustomA2DP is not a commercial product: no ads, no trackers, no subscription. A donation is your gratitude for our work and a wish to support the project; your support is a sign to us that the dozens of BSODs and debugging sessions were not in vain. Roadmap: driver signing in Microsoft, adding APTX and LDAC codecs. Send your suggestions and reports about the driver to support [at] customa2dp [dot] com.
%ProgramData%\CustomA2DP usually resolve an issue faster than anything else.