i seem to remember having had a similar thing with the card player: sometimes it would stop looping and the only way to restart would be to reload the file.
This was on the latest 0.5 firmware, in a patch with 3 or 4 card players playing simultaneously, and the whole patch was rather high on CPU.
IIRC, the bug with card player occurred when saving/loading a snapshot of the patch, not during normal operation. Maybe it’s related ? At the time I ascribed it to excessive i/o activity on the sd card and did not think twice about it.