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that's what it sounds like.  My battery lasted just a bit over a year.  It's really easy to do if you want to do it yourself.

Unfortunately, this is what my Cyclops power tap experience was like.  All fixes were temporary.

Hope a new battery helps you.

Actually- when the battery dies... it generally just dies.  but replacing the battery is easy and worth a shot.

I've got one other thing to try.  If you are using a Garmin Edge 500 rather than the LYC, go into the bike profile menu and check to make sure that the Garmin isn't searching for an ANT+ device that isn't there.  i.e. if you don't have a GSC10, make sure that it's turned off.

if this doesn't work- then download the file and capture one of the dropouts and put it up over on the garmin forums.  there are a few sharp people over there that know this stuff inside and out.

or call Cycleops.  Not sure how their tech support is.

This is my experience, once it goes to zero, that's it, it doesn't come back on.  It takes about 3 minutes to change the batteries and they are extremely cheap, so it's definately worth a try.

I always log my hours/miles of my PT wheel in my training log, and in general, I get about 200-250 hours out of a new set of batteries.