There was a similar thread on this (No Sound…) but no responses. Details about my system and settings are below.
I can’t get any sound to play from my Audacity files. All was working perfectly until about a week ago. Can’t think of anything I changed, added, deleted, etc. that would have caused the problem to occur. The recording and playback monitors show that my vocal was recorded and is playing, waves are showing up, and even the ACX check works on the file. But there is no sound from the file, whether:
(i) using my headphones and my ProSonus AudioBox USB, in which case my Inputs are set to AudioBox 96 USB and Output is also AudioBox 96 USB (both in my Audacity settings and my Macbook Pro Sound settings), or
(ii) using my headphones plugged directly into the laptop, in which case my Input is the Internal Mic and Output is Headphones (or internal speaker), (both in my Audacity settings and my Macbook Pro Sound settings), or
(iii) using no headphones and no ProSonus, and just listening through my Macbook speaker, in which case my Input is the Internal Mic and Output is internal speaker (both in my Audacity settings and my Macbook Pro Sound settings).
I can hear the files play after converting them to mp3 files. I changed my headphones, but didn’t help. I get sound through my headphones (whether through the ProSonus or my laptop internal speakers) when listening to another app like YouTube.
I have shut down and restarted audacity. I have shut down and restarted my laptop. I have opened and tried to play other, older Audacity files (same problem). I have recorded new Audacity files to make sure my old files weren’t just corrupted. I’ve run the Rescan Audio Devices, and my Playback Device and Recording Device are set to AudioBox USB 96 when using my ProSonus. The recordings are set to Mono.
I have uninstalled and reinstalled Audacity, more than once.
Details of setup:
Macbook Pro 2017
Operating System: Ventura 13.0.1
Audacity version 3.2.2 Downloaded again today 12/16/22)
Help, please! 
Appreciate it.
Jim