Sound can be heard on recorded views but there is no sound from any of my cameras on live view. The 2 way talk does not work either
That is very unusual to hear @Tahoe216. I recommend uninstalling and reinstalling the app on your mobile device. If that does not improve audio, please check your network signal strength and speeds to ensure your connection is sufficient for audio. Let me know how this goes! 
I’ve tried that already. The sound come back on the first time I reconnect, but then goes out again.
I have a 10plus android,in live mode it is using the in call sound and on playback it’s in media playback,it did not use to do that,no sound on live setting.
It appears to be a Samsung issue. I have 2 Samsung phones that do it, but my lg works