Fire TV Kodi audio doesn’t always work but other apps audio works?

Have a Fire TV box gen 1 rooted. FireOS 5.0.5.1 which I updated about two months ago from a very old FireOS 3?

Anyways I had Kodi 16 installed before I updated FireOS add audio didn’t work in my movie files. GUI sounds work and other apps like Plex and Netflix and ESPN audio work.

I then updated Kodi to 17.1 and finally was able to get audio on my files. But after a few hours or days of use the audio won’t work again but works in other apps.

What is weird is I need to reboot the Firetv twice to get audio working again. I have tried switching HDMI ports and cables and nothing solves it. Kodi is the only app that gives me the problem.

Any suggestions what could be happening?