I need a replacement speaker (L earpiece) for Sennheiser HDR 65 wireless headphones. Do you have a source for Sennheiser parts?

SOURCE: Bad battery for my Sennheiser HDR 45 headphone

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

SOURCE: Bad battery

A replacement battery can be purchased from Sennheiser for $20.00.
Battery Part Number: BA 151
Sennheiser Link:
http://www.sennheiserusa.com/newsite/productdetail.asp?transid=004146

SOURCE: sennheiser hdr 30 battery

you can check in ebay battery # ba151

SOURCE: No sound coming through my Sennheiser wireless headphones

Turning the transmitter on and off (Fig. 5)
Turn on the sound source. This automatically activates the
transmitter and the green LED “ON/OFF” lights up. If the sound
source is turned off, the transmitter is automatically deactivated
after approx. 3 minutes (the LED “ON/OFF” goes off).
Note: The automatic level control only functions if the volume of the
sound source is sufficient.

SOURCE: My cordless HDR 130 Sennheiser headphones no

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.