I’ve switched to a new daily driver phone (Fairphone 6), and I’m seeing this problem there as well. To clarify the steps of what I see a little (as far as I can tell):
Open Arc after not using for a few hours
Start playback
Lock phone
Playback stops after some seconds and Arc notification disappears
Playback resumes when reopening Arc but notification is still gone
Thanks for the the ping letting us know that the issue is still ongoing. I’ve recently spoken to the team regarding your report and I am trying to get this issue prioritized for the dev cycle. Thanks again for the steps, and I remain hopeful that we can make progress on this sooner rather than later.