Thank you for your reply!
Yes, it does this daily over the past couple weeks (i.e., crashes after an hour or so, with the same symptoms, except that it would be while streaming a different song.)
My music files are mostly in Apple Lossless format, with some WAV files.
I’ve stopped the automatic scan because it would often fail to add the iTunes playlists (the only playlists I use) every other time it scanned. I set the Rescan Interval to zero and manually initiate a scan, as needed. It usually take two scans. The first time, it fails to add the playlists; the second time it adds them correctly.
I’m using the “stable” version downloaded via Roku Soundbridge forums website. In “About” it says: “Firefly Service 1.0 svn-1359”