Naim streamers: Unsupported format: Stop or Skip track?

A quick question to streamer owners out there. What has been your experience with the above? I leave my music playing 24/7. Sometimes I come back (e.g. next morning) and the music has stopped. Sometimes it can play for days and days without a problem. I have not been able to weed out the rogue tracks of my system (i.e make sure 100% of tracks in my folders are supported) so I am not sure why this is actually happening.

Have you ever experienced this behaviour from your streamer? ('me no like format, me stops')

An alternative question would be; what is Naim streamers' programmed behaviour when they encounter a track in a format they do not support? Are they meant to stop playing until one presses play again or 'next'? or are they programmed to skip it until they find something they do support?