The ARC problem is currently a known issue that has something to do with Qobuz and affects several (many?) users. Though the precise cause is as of now unknown. This is being tracked here:
There was also another, possibly related Qobuz issue caused by Qobuz reorganizing servers. This affected not just Roon (the regular Roon, not ARC). It is partially improved but not fixed for everyone and is being tracked here:
Qobuz published this update:
For your other issues, you won’t make much headway here in the Uncategorized category of the forum. Your experience is not normal and I’d suggest opening a tech support case: