I've been training with a HRM for a few months now.
Over the last few weeks I've found my HRM occasionally not working, or 'sticking' on particular numbers, irrespective of effort.
I checked the contacts were moist - no change. I ended up buying a new (and expensive!) HRM in frustration. This one seemed OK, then did the same thing...!
I think I've managed to figure out in the end that it was static from my riding tops (basically the HRM would start working again if you held the top away from your body)
Trouble is, I'm not sure how to stop this - I even bought some anti static clothes spray which doesn't seem to work. It's worse when I ride my road bike for some reason (flapping top in the wind?)
Anyone had this, got any thoughts on it? I wouldn't be so stressed if it wasn't a crucial part of my training/riding for a stage race I'm doing soon!