SQ is better with internal SSD vs NAS

This has nothing to do with SQ. It’s because NAS are exceptionally bad for watching filesystems properly, so Roon can’t watch for new files automatically. The “new file” experience is much worse on the NAS than it is on internal storage or USB storage.

That tells me the extra network traffic used by Roon accessing your NAS is somehow impacting your Bryston’s outputs.