Audio / Video goes out of sync after several hours / days - Multicast source

### Issue description
After from 1 about hour to sometimes a day, the audio and video goes out of sync during playing.
This occurs in our app, and the Exo Demo.
The channels are free to air DVB-T
We are using Multicast sources.
Changing 'channel' / Source corrects the problem until it occurs again.
The issue is not evident on Android / windows VLC

### Reproduction steps
Watch a DVB-T multicast source over several hours.
I have not figured out how to reproduce.
I have tried disconnecting the antenna from the tuner headend for short periods and have not been able to reproduce.

### Link to test content
The following link contains 3 videos.
1. Of Sony TV with AV sync issue (Phone recording)
2. Of Nvidia Shield playing same stream in sync (Phone Recording)
3. Recording of TS using VLC recording functionality

All 3 recordings were taken within minutes of each other on the same channel.

Note: 1 and 2 have very low audio. You can boost in VLC when playing. I will also re-record when the issue occurs again.
https://mega.nz/folder/XcZgjJTS#YF0pQWvBLGq2kstvVt4h2A

We are endeavouring to use wireshark to capture the traffic between the switch and the TV. This will be provided as soon as available.

media.exolist.json is in the above share.

### A full bug report captured from the device
https://mega.nz/folder/XcZgjJTS#YF0pQWvBLGq2kstvVt4h2A

### Version of ExoPlayer being used
Exo Demo 2.11.5
Our app V2.10.8 (Dec 2019)

### Hardware platform:
Sony Bravia 55" Android TV. V8.0.0
Nvidia Shield V8.2.0 & 9

Thanks for your assistance.