Mike -- Hobert

Have you Gents tried downsizing your computer connections -- i.e., getting back to basics -- temporarily? If not...
1) Try disconnecting every computer peripheral except mouse and keyboard.
2) Plug in a pair of stereo headphones or self-powered speakers in the computer's 1/8 inch stereo audio out jack
3) Reset any computer audio Playback settings if you must.
4) Restart your Mac (only as an option)
5) Launch Resolve with a NEW PROJECT
6) Drag into Resolve's timeline, an Audio/Video Clip onto Track V1/A1 respectively
... and also drag an Audio-only clip (onto Track A2)
7) Ensuring no MUTE facility is engaged in any of Resolve's half-dozen pages, press PLAY, from the FAIRLIGHT audio page.
Observation:
Does playback interrogate any Audio Track Headers' meters to move in that FAIRLIGHT Page?
If Yes, but no sound gets through, check all audii options again (making certain Resolve's Project Settings are pointing to your computer's native audio device.
If successful, gradually add a peripheral checking Resolve's audio behavior and its audio settings relative to your
desired audio device's settings., until you find a peripheral device and/or its drivers is at fault.
That's how I'd begin problem-solving your issue of "no sound", before experimenting with the possibility the specific OS and audio drivers or even some peculiarity with your specific Resolve version are at fault. Hete's praying that approach helps either of you in trouvkeshooting...
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