Not sure if this is specifically connected to B107, but anyway - entire phone becomes extremtly warm during download (to the level of it is almost too warm to touch the display).
No such issues on any other of my apps; so seems to be directly related to Roon ARC and download.
Funny, I just noticed this morning the iPhone XS that I use was getting warm this morning during a download.
I removed the case during the download but it didn’t help much.
I did a test by exiting the Roon ARC app (which still downloaded), temperature dropped to normal level very quickly.
Also I noticed display started flashing during download in Roon ARC, while it stopped flashing if I attached the phone to a charger.
Edit:
Also noticed that download of tracks actually used so much CPU that it did not manage to increase battery level while phone being connected to charger.
