A client has a pair of Sennheiser RF headphones, TR130, that simply appear to be dead, and I was wondering if any of you can confirm what I'm finding. Actually checking the audio wiring is a MAJOR pain as a cabinetmaker completely did not understand how to make a cabinet for components. That's another subject, but it leads me to ask if I'm correctly interpreting what isn't happening with these headphones.

They stand shows power. It shows charging. The batteries read about 2.9 volts when the thing is turned on, which indicates that they are charged and can deliver whatever current the headphones require.

But I get zero sound. Not only when an audio source plays, but also when I hit the TUNE button to tune around. You usually get static from being near but not quite right on the right frequency, but again, zippo.

Am I right that these are just plain dead? They're only a couple of years old and have not been mistreated at all. In fact, they've been used so little that the only question I had was whether the batteries are any good, and they are.

Thanks for any experience you might be able to share.