I can confirm the latest beta 4.36.12.9751 finally fixes the audio playback with the V3 Floodlight. I am going to do further testing before I recommend others to try it.
Cam V3 FW is 4.36.12.9751 beta
Floodlight FW is 1.0.0.55
App version is v2.50.2 (442)
Plugin version is 2.50.0.24
Please note the previous beta 4.36.12.9357 firmware introduced a weird behavior like the OG cams where after 30 min of internet outage, the micro SD recording starts recording into randomly generated date folder with a wrong timestamp. As a result, you couldn’t play back the footage in the app and you have to physically remove the micro SD card to play it on a phone or PC. You can technically play the recordings back in the app if you know the specific date of the random generated folder.