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Question: I bought a second RS 170 headset to use with my 170 base & transmitter, I installed the batteries turned on power no sound from the new headphones? The other Headset worked fine! Switched Batteries still no sound?
Document: Including batteries of this caliber shows you they're serious about quality.TIP: To turn on the transmitter and headset, HOLD the power buttons down for about 1 second. Because the power buttons are "multi-function" buttons, how long you hold the button down changes the function.UPDATE 2013-12-20: I'm lowering my rating to 4 stars. I have had some issues with this that I never had with the RS120, and that's getting no sound from the headphones.
So i needed wireless headphones so that my wife and I could watch TV without bothering my daughter while doing her homework. These were the only ones that could be connected to more than one headset.I followed the instructions and pressed power on button on transmitter. LED blinked approximately one blink per second. I then turned on the headset that came with transmitter while being very close. Headset's LED also blinked at about one blink per second. Very quickly they were connected and blink rate was about one blink per five seconds.
Her advice was what caused me to try a different brand. Now I have gone back to the Sony and black specks are welcome, at least by me..I have had the Sennheiser headset too long to return because I had a difficult time getting it installed and working. I had to refer to the Sennheiser CD and the TV manual numerous times before finally getting the right combination. The sound quality of the Sennheiser if just fine. It is all the nuisances that turned me off.
I charge it every night after I'm done with it. I've had the headphones on for the entire day, and it was still running fine when I'm done. The batteries also use standard AAA batteries and they're easy to replace, and that's very important for me, because it ensures longevity and I bought these headphones with the intention that they will last long.The headphones are very comfortable as well. I like the type of headphones that cover your ears, and these headphones do exactly that.
On multiple occasions, I have accidentally turned off the headset instead of changing volume. Big design flaw on Sennheiser's behalf.- I liked the idea of having a wireless base station to recharge the headphones on. No messing with USB cables to recharge! However, each time you use the headphones, you have to re-link them with the basestation. You have to push a power button on the base station until it starts flashing green, and then push a power button on the headphones until they flash green.
Takes a long time to charge, and a big hassle overall. I don't use the base charger at all now after trying it for a couple of days. Swapping batteries is much easier.I love this headphone, very good sound. Also very comfortable.Con:There is one glaring problem. Quote from another review:"The other annoying problem is once you turn off the headset, or turn off the input device at the transmitter, the system reverts to standby mode within 5 minutes.
Sennheiser RS 170 Digital Wireless Headphone with Dynamic Bass and Surround SoundI have owned many different brands of wireless headphones over the years and they were OK at best. (Sony, JVC, others) When looking at buying a new set, I was pleasantly surprised the new technology had discovered a way that didn't hiss and make static noise when you turned your head in certain directionsThese Sennheister RS 170 sound great!...
The system was very simple to hook up, is easy to use and has a very durable feel. I think the sound is excellent and I enjoy it. Although I have extreme audiophile friends who would undoubtedly snicker at that statement. The headphones are over the ear and are comfortable and have a sturdy feel. The built in recharging stand on the transmitter and the rechargeable batteries in the headphones have worked great.
I ended up having to have a friend who is in the business give me a splitter and that has worked out fine. (These are available on Amazon)  Second, turning them on for use, ('pairing' in their terminology) each time you use them is a bit tedious; you can't just take them off the charger and use them.
This is my third pair of Sennheiser headphones - my first two were cheaper versions and each lasted about a year and a half. The first died when the batteries just smoked the headset itself, the second died when the transmitter just stopped working.I like this pair pretty well, but like others am not really happy with the buttons - really difficult to figure out which one you want to press without taking the headphones off.
Answer: I saw this on a review someone had written about having two pair of headphones with one receiver:When it comes to using multiple headphones for the receiver, the manual provided with the extra pair is useless; you have to use the digital manual for the transmitter. Apparently, the transmitter automatically starts up in single headphone mode; I'd turn on both, but only one would receive, then turn off the working pair and the other pair would start working. After reading the manual, which tells you, with both the headphones on and the transmitter off, to turn on the transmitter, then push the power button on the transmitter again to activate multiple headphone mode. After doing that, both headphones started working perfectly. In multiple headphone mode, bass boost and surround sound is activate/inactive for all headphones, while volume is controlled independently for each headphone.  Associating the headphones using the manual provided was somewhat difficult because the manual, although 130 pages long, only has about 8 pages in English, then 8 pages each in 14 other languages. The part about associating is a single page in the middle of the manual, all illustrations, that pretty much tells you to turn off both the headphones and the transmitter, then, with the two within 1 meter of each other, hold the power button on each for 7 seconds.