On my Macbook Pro, running MacOs Catalina, Strawberry sometimes starts using up 100% of my CPU and becomes unresponsive (the active track plays, but no controls work. When the track finishes, nothing happens).
Running Strawberry from the command line so I can see the debugging output, there is a common theme: the crash always seems to occur shortly after a failed URL transfer, e.g. a failed lyric look up. I tried disabling all lyric providers and everything worked until it ran a track for which there is no cover art. Again there was an error inthe output (here: 08:10:51.792 ERROR MusixmatchCoverProvider:227 Musixmatch: "Error transferring https://www.musixmatch.com/album/unknown/settlers3 - server replied: Not Found (203)") and shortly after the CPU usage went up to 100% and Strawberry stopped responding.
I guess there is a workaround for now, which is that I disable all lyric and cover lookups, but this appears to be a bug to me