Re-enable audio ducking for proxied x86 speech synths#19672
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seanbudd
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michaelDCurran
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This reverts commit 5306000.
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…026.2 as it is not stable enough yet. (#20206) Fixes #19667 Fixes #19819 Reverts #19672 Summary of the issue: Experimental code was recently added to NVDA (after 2026.1) that caused the 32 bit synthDriver shim to send its audio back to NvDA for playing, rather than playing it directly in its own process. This was done to test / prepare for the time when add-ons would be running in an app container, and therefore probably would not have direct access to the audio device. However, currently this code is still quite unstable, causing NVDA to freeze when rapidly changing the speech rate, or arrowing up and down in lists, when using sapi4 or 32 bit sapi5. This instability is most likely a similar issue to what was fixed in pr #19609, where RPYC is handoing the return of a call on the wrong thread. But in this case, it is calls to/from nvwave in NVDA's process. Description of user facing changes: Description of developer facing changes: Description of development approach: Simply instruct the synthDriver process not to install the nvwave proxy that brokers back to NvDA. Reverts Re-enable audio ducking for proxied x86 speech synths #19672 so that 32 bit synthDrivers suspend audioDucking while they are running, as audioDucking cnanot be supported without brokering audio.
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Link to issue number:
Follow-up to #19665
Summary of the issue:
#19665 prevents audio ducking when using a proxied SAPI4 or SAPI 5 speech synth, as it does not work correctly on betas due to the synth outputting sound out of process. However, as alpha builds broker the audio from from the 32-bit host process and output it in process, audio ducking works correctly.
Description of user facing changes:
Audio ducking again works on alpha builds when using a SAPI 4 or 32-bit SAPI 5 synth.
Description of developer facing changes:
None
Description of development approach:
Reverted the changes to
source/_bridge/components/proxies/synthDriver.pyintroduced in b0228fe9aa.Testing strategy:
Built a self-signed launcher and installed NVDA. Switched to SAPI 4, played some music, and tested that all 3 ducking modes work as expected.
Known issues with pull request:
None known
Code Review Checklist: