I have a Beocom 6000 base (triangle thing which includes a charger and base, the second is charger only) and two handsets; I think one handset is mark 1 and the other is mark 2 (I've flipped the battery cover and seen two config holes on one and only one hole on the other). I am not sure if the base is mark 1 or mark 2.

Previously, I was unable to register the mark 1 handset with the base but I reset the base and both handsets using the DOT 70008 and DOT 70009 commands which has fixed this problem. I can now register the mark 1 as handset 01 and mark 2 as handset 02, and vice versa.

However, the problem is that after a while when I try using the mark 1, I get an engaged dial tone noise. Sometime you can leave it, or keep trying, and it generally does recover and reconnect. The mark 2 is always fine. Has anybody experieced this? Any suggestions for a fix? The battery is weak in the mark 1 so when I get home I will try swapping the power packs in the handsets.