Bad battery Battery doesn't hold a charge anymore (three years old) I want to purchase a new battery for my HDR 45 headphone Sennheiser.

If you twist the earpiece,one of them has two NIMH AAA batteries ,worth checking out if these are gone ,which is what happened to me.I was about to bin my rs130's and just stuck two new rechargeables and the earphones are working again!!!!!

As for $20 dollars from sennheiser for replacements!?!?!?
You should pick up two NIMH batteries for a couple of bucks on ebay or amazon.DO NOT USE ORDINARY BATTERIES!!!!!

assuming the battery is charged, have you tried to switch to a different frequency band, etc.?
check page 28 of the user manual for possible actions when there is no sound in the headphone.

You can download the manual for the product from the below link:

http://www.wireless-headphones.net/rs-45_manual.pdf

Hope that allows you to resolve the issue. Please revert back for any further assistance.

Regards

Anand

My Sennheiser HDR 140 headphones charge whenever you hang them on the charger. The charger will "trickle" charge them to keep the batteries fully charged. If you find when you use it the batteries discharge quickly it's time to replace them.
My batteries are about 2 years old and I still get about 8-10 hrs of use before needing to recharge

check on radio shack

The batteries are at end-of-life OR your charger has failed.

Forst replace the batteries... they are MOST likely bad. Charge the new ones before using.

Twist the pad counterclockwise on the left earpice. You'll find the batteries underneath.

It's been a while since you posted this, Were you able to get the problem solved? If you are in the NY metro area, I have an extra T6-9 and I could test to verify if the proble is with the headset or the Freesound unit.

You can buy the HDR 120 model which is basically the headphones lone
These will work with the base in conjunction with the set you have now.. or as a replacement
You can also buy replaceable ear cups for less than 20 dollars (check the Sennheiser website)
Finally you may want to replace the rechargeable batteries in the headphones you have
Just make sure you replace them with the exact type.. I believe those are NiMh AAA
Pop them out and go to any Battery Plus or Radio Shack.. a new set probably run you less than 7 bucks
My point.. for less than 30 dollars you can have your old headphones working and looking like new ones
Give the new batteries an overnight charge before using them

Good luck

A replacement battery can be purchased from Sennheiser for $20.00.

Battery is: BA 151

Sennheiser Link:
http://www.sennheiserusa.com/newsite/productdetail.asp?transid=004146