Update works good here. No audio problems with regular phone calls.
I notice the same problem when using the Jitsi app for video calls. My voice is extremely low, almost not hearable to others. When using Jitsi web it is working fine.
So obviously there is some incompatibility between the FP3+ and apps used for video calls (Jitsi, WhatsApp, Signal, …).
Beside of that I am almost happy with this update - except the clock-space-bug, which is still annoying to me 
And I guess the settings-suggestions-bug is still there (the workaround mentioned in this thread seems not to work anymore - at least in my case).
Oh, and bringing back WPA3 would also be nice (as it is a core feature, officially introduced with Android 10)! This worked before, but not anymore since v77 and not in v84, too.
Maybe @formerFP.Com.Manager can have a look into these bugs.