This happens to me too. I’m listening from my Roku. After a couple hours it goes to the next tract but the sound is gone. It looks like it’s playing the next song but it just goes silent. I am using the free service and I thought about subscribing but it sounds like the paid subscribers have the same problem.
Moderator Edit: Changing title for clarity
@Ffebles I moved your post over to the Other Devices space.
First, please try a few standard network troubleshooting steps:
If you are still having trouble, please try using the steps in the following link to update your Roku software: https://support.roku.com/article/208755668-how-to-update-the-software-on-your-roku-streaming-device.
Finally, try deleting the Pandora channel from My Channels, and try re-adding it from the Channel Store. (You can find the Remove channel option by pressing the * key on your remote while the Pandora channel is highlighted on the home screen.)
Let me know how it goes.