This is not a release. It is a one-off test build for #5713, published here only so the affected operators can download a single file without a GitHub account. It is unsigned, it is not in the update channel, and it will be deleted once the fix ships in a real release.
What it contains
PR #5719 at 97c941f2, on top of v26.9.3:
- The Windows CW sidetone default goes back to
QAudioSink. v26.9.3 was the first Windows build to ship PortAudio at all, which silently moved the sidetone onto that path for every Windows install. Because the sidetone starts when RX audio comes up, it ran on every connect whether or not you use CW — and it crashed withSTATUS_HEAP_CORRUPTION(0xc0000374) on at least three machines. Linux and macOS are unchanged; they keep PortAudio. - PortAudio now records what it saw before it can die — the host APIs and output devices it enumerated, and the exact stream parameters it opened with, each flushed to disk immediately so a hard kill cannot discard them.
This takes the crash off the default path. It does not explain the heap corruption, which is still open.
How to use it
Unzip anywhere and run AetherSDR.exe in place. It does not touch an existing install in C:\Program Files\AetherSDR.
If you already applied the CwSidetoneBackend=QAudioSink workaround, clear it first — this build reads the same settings as your installed copy, so your saved value would mask the new default and you would be testing your own workaround instead of the fix:
AetherSDR.exe --config unset CwSidetoneBackend
Full instructions, including the optional second test that would help find the real bug, are in this comment on #5713.
Verification
SHA-256 68f5d72ae7b733edde2f3223118730e3a6d457b3bb5717d1db4e5dd433d6ee16
Built by Windows Installer run 35038022128 from fix/5713-audio-diagnostics. This file is byte-identical to the Windows-Installer artifact on that run, renamed.