According to the BioCor manual:
"Channel 1 (additional inductor): works for 5 minutes (EHF is emitted) and then it is switched OFF. Channel 2 (inductor on the headset): works in cycles – 1 minute in active regime (EHF emission), then 1 minute in passive regime (no EHF). This cycle is repeated 3 times."
Thus, the first channel works for 5 minutes, and the second either works or is paused.
The limit of 5 minutes is determined by the necessity of dozing the High frequency impact.
You can listen to any music using a BioCor device, not only the music generated in the Bio-Well program. As for the songs, they can be of absolutely different duration.