Audio stops after 3:06:24 (3 hours, 6 minutes and 24 seconds)

[owl770]

I am running rtl_fm_streamer (V0.0.6) on a Rpi 3B+. I am using mpd (on another Rpi) to play the radio stream. It all works perfectly until 3:06:24 of runtime. The audio stops. mpd reports alsa_output: Decoder is too slow; playing silence to avoid xrun. If you do mpc stop and then mpd play, it all starts working again. The 3:06:24 limit occurs consistently (100% of the time). Listening to the stream on Chrome on my Mac exhibits the same behaviour (audio stops at 3:06:24).

Does anyone have any suggestions as to where I should start looking for the problem/cause?