You could edit the song and delete then add the repeats back then Done, Save it, then check play. Also you could make a new song with a few measures and put in some repeats and check. Also play a few other songs with repeats to check. To save time, use a high BPM to test.
I presume you have not edited the song; if END has been added in song edit and repeats set to 1x it might not play correctly for instance.