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Question: My headphones worked wonderfully until I had to replace the batteries.  Now, they are hard t tune,  spotty reception, don't charge well, blurry sound
Document: I ordered the RS 120 headphone with transmitter/charging cradle for me, and the HDR 120 headphone w/o transmitter or charging cradle for my wife. The RS 120 worked perfectly right out of the box. The HDR 120 refused to charge its two AAA batteries on the cradle as it was advertised to do. Therefore, actually I don't know whether or not the HDR 120 worked or how well. Amazon sent me a replacement HDR 120 by priority FedX.
I bought this headset to replace a radio shack wireless headset where the batteries were failing. I like the Sennheiser for its quality, the fact that it sounds great and for the fact that it uses AAA rechargeables (comes with it) that will hold a charge for more than 24 hrs of use, and they are easily replaceable when that time comes. The sound quality is excellent... good bass and the highs are clear.
The sound is very good and these headphones can withstand a lot of abuse. This unit replaced headphones that have received lots of usage over the last three years. I have replace the rechargeable batteries at least once. I wish my other electronics were this reliable.
A wonderful product for me. Being hard of hearing (nearly totally deaf in one ear) I have tried several devices to enhance TV watching. These headphones are the perfect item for me. I can use them while my wife can use the speakers at a sound level she is comfortable with. The headphones are comfortable for long periods of time and I can still easily shut them off during commercials. I can tune them in with ease and the sound quality for me is great.
I have owned Sennheiser RS120 headphones and they help me to hear better while watching DVD's (I have some hearing impairment). However, when watching with my spouse, I couldn't use the headphones and I lost some of the dialogue.The additional headphones have solved the problem. They perform as well as the original phones and charge on the same cradle (at a separate time). Folks who visit us and try the headphones rave about the sound quality.
This was my second set of two headphones. First set is about 5 years old, maybe older, and both headsets still work great. Bought a second set of two for our RV so we don't need to disconnect and reconnect after traveling. Never had any problems, ever, for over 5-years of  pretty constant usage and haven't had to replace batteries. I watch a lot of TV & movies and often wear the headphones in the garage listening to Fox News while working on projects.
this was a replacement headphone as we had the base from prior purchase. it fit and worked great. My husband is very pleased to have such great sound wi the Sennheiser HDR120. He is hard of hearing and he can place the headphone on and adjust the sound to his needs. very useful and a great sound
While I expected some interference, being it uses radio waves, I was impressed that it is minimal. You have a dial on the right head set that you must tune in the head set to. If you experience significant interference (which I didn't)you have a slide switch on the base to select one of three channels, so the anti-static noise options are built-in.The head phone are very light weight and fit great. As for the sound, I've never heard stereo so well.
Product delivered on time and in good shape. When it came to charge the batteries, the headphones won't charge. I have to recharge the batteries on an old set and switch batteries. What a pain. Not happy at all.
I had read some reviews saying there was some "hissing" Well I don't have any of that. The item is plug and play ready to use. Within 10 minutes of opening the box and installing they worked better than I ever expected! Sound clarity is perfect and the weight on your head is minimal. I work nights and when I get home early AM I like to watch movies without disturbing my neighbors in my duplex. Now I get the sound I want and more.
Answer: Try changing the "channel" (1,2,3) on the charging stand.  My dad's did that and I changed the channel and they worked fine.