
Hello,
I had the same audio sync issue with 15b5. My footage is Prores from an Atomos Ninja 2, separate wav audio from a Zoom H2n. Synced the clips with waveform in 15b4, lost sync with 15b5. Reinstalled 15b4 which fixed the problem. I am using the free version of Resolve.
I had another issue with fullscreen playback (on GUI monitor), where playback would get stuck on play, couldn't exit fullscreen, couldn't stop playback. However, the audio issue was a showstopper so I went back to 15b4 right away, so I don't have any more information about that.
-Timo
Mac OS Sierra (Hackintosh)
Intel i5-6400K 3.5 GHz
32 GB ram
Radeon RX480 8GB