Is there such a thing as a TV headphone jack extender cable, or is there a way to have the transmitter for my wireless headphones plugged into the jack AND hear the TV?

No it isn't normal. This is a set that you plug into the television and it transmits the signal to the wireless headphones. It sounds like the transmitter unit is picking up interference. We can test it! The headphones can be connected directly with a wire. Try that on the television earphone jack, or on a cellphone, a radio, MP3 Player or a computer audio jack. If the audio is clear, with no hiss, then you know the problem is the transmitter unit. Move it as far away as the wires allow from the television and anything electronic.

It is advertised here on Amazon and the diagram shows how it can be connected, 4th image down on upper left.

5-in-1 Wireless Headphones Headset MH2001 MP3 MP4 ...

Amazon.ca https://www.amazon.ca > Wireless-Headphones-Heads...

5-in-1 Wireless Headphones Headset MH2001 MP3 MP4 PC CD DVD Audio TV FM Radio-Listen to Music, Chat Online & Monitor Other Rooms! : Amazon.ca: Electronics.
More here regarding the hissing sounds

https://www.google.com/search?q=mh2001+wireless+headphones+hissing+sound

I used an 1/8 inch male plug into tv and then into headphone xmtr.
amazon has lall cables and adapters.

here is link to instructions
copy and paste

https://fccid.io/ANATEL/00916-12-07356/Manual/43CEE361-CE0E-4C13-998C-DDDC6A4E2E2C
https://en-au.sennheiser.com/how-do-i-set-up-the-rs-120-wireless-headphones
https://www.youtube.com/watch?v=IkEGgXD__NI

Hi Richard,

First, you'll need to determine which type of input(s) the wireless headset transmitter has. Most common is the 3.5mm stereo plug designed to slip into the headphone jack of a TV, MP3 player, cell phone, etc. Some transmitters have adapters in the box to allow connecting to the Left and Right channel RCA / phono style jacks found on other components such as CD, DVD, VCR, Stereo receivers / amplifiers, etc.

You'll need to find OUTPUTS of the CD and TV that match the plug on the wireless headset transmitter. If yours doesn't include adapters to go from say the RCA jacks mentioned above - to whatever connector that the transmitter input has - you'll need to go to your local Radio Shack store or similar store to see if they can provide an adapter that will allow you to connect.

Here are a couple plugs / adapters:





Above: A "3.5mm stereo patch cable". Your transmitter may have a cable with an end like this to plug into the TV's headphone jack.




Above: A "3.5mm female stereo jack to RCA stereo male plug" adapter that would allow the top cable to connect to the Left and Right audio output jacks on a typical CD, DVD, etc. device.

These cables / adapters are typically $5 to $10 maximum.

I hope this helps and good luck!

Using the appropriate cable for the transmitter that came with the wireless headphones, connect one end of the cable to the AUDIO OUT jack on your TV set and the other end to the AUDIO IN jack of the transmitter. If your headphones came with rechargeable batteries, don't forget to charge them before using the headphones.

H

Instructions
1
Set up the transmitter. Wireless headphones rely on a transmitter that sends audio via infrared or radio waves to your headset. Use the digital audio output (coaxial or optical), RCA outputs (red and white) or headphone jack on your TV to connect the transmitter. The connection will depend upon which outputs are available on your TV and/or the transmitter.
2
Use an RCA-to-headphone adapter. If you don't have a headphone jack on your TV and the transmitter includes only a headphone connection, connect an RCA-to-female headphone connector. This will allow you to plug the wireless transmitter into the female headphone end and then hook the RCA ends into your television's audio outputs. You may also need a 3.5 mm (mini jack)-to-1/4-inch adapter if the headphone plug on the transmitter doesn't match the television jack.
Read more : http://www.ehow.com/how_4883556_use-wireless-headphones-tv.html
3
Set the transmitter on top of, or next to, the television. For infrared transmitters, you'll need a direct path between the headphones and the transmitter. Placing the transmitter on or near the TV will allow you to take advantage of the clear path you already have.
4
Plug in the transmitter and turn it on. Charge the headphones if necessary.
5
Turn on the headphones. Adjust the volume and settings and you're ready to watch TV.
Read more : http://www.ehow.com/how_4883556_use-wireless-headphones-tv.html

good luck

Headphones are a convenient way to experience audio-rich entertainment on your own terms. Headphones allow you to customize your listening level without disturbing other people in your general vicinity. Headphone cables can be a hassle, however, so many new headphone models feature a wireless connection. PCs tend to be wire jungles, so eliminating one wire from a potentially jumbled mess can be an intriguing feature of wireless headphones. Connecting wireless headphones to your PC allows you to take advantage of the benefits of listening to your movies, music or games through headphones without the struggle of the headphone cable.

Charge up or place batteries in your headphones and transmitter. Wireless headphones require power to function. Many wireless headphones come with a charger base. You need to charge your headphones before you attempt to connect them to your PC. Some wireless headphone models require batteries, which you must install before you connect the headphones to the PC. Connect the transmitter to your PC. The transmitter may connect via the PC's headphone jack or USB port. If the transmitter connects to the headphone jack, plug it in and check your headphone's user guide to verify how to synchronize the headphones to the transmitter. If the transmitter connects via USB, you will likely need to install software to use your wireless headphones. If your wireless headphones are Bluetooth-compatible, continue to the next step. Pair your headphones via Bluetooth to your PC. If your PC is not Bluetooth-equipped, you will need to install a Bluetooth USB dongle. Turn on your headphones and open the Bluetooth software on your PC. Scan for Bluetooth devices from your PC. Your headphones should appear. Select the headphones and follow any further instructions to complete the pairing process. Test the headphones. Pick out a song or a video and play it on your PC. Connect your wireless headphones and verify that you can hear the audio. Find the volume controls on your headphones and adjust them to make sure the volume changes correctly. If your headphones are not functioning properly, verify that the headphones are turned on. If the headphones are on and you do not hear anything, verify that your transmitter is functioning properly and that you have your volume turned up on your PC. Recharge your headphones when you are finished using them. To ensure that the headphones are ready anytime you need them, you must always place them on the charging base when you are finished using them. If the headphones are battery-powered, be sure that you always have spare batteries on hand. Hope this helps.

The audio jacks on the TV are most likely inputs, not outputs. They're meant to take the audio signal from something like a DVD player, along with the video input on another jack, so you can play it through the TV. There isn't an audio signal coming out from those jacks, and if you connect your headphone transmitter to them all you'll get is silence. Almost all sets now have at least one set of AV inputs, but most don't give you outputs. The manufacturers figure the TV is just a display device, and not a signal source.

Unfortunately, there isn't any easy way to connect your wireless headphones if the TV doesn't have audio output jacks or a headphone connector. If you're comfortable with soldering and willing to do some modification to your TV, it's possible to add a headphone jack. Most people don't want to start tinkering with their sets, though.

If you're using your TV on a cable system without a converter box and the cable hooks right to the set, you're out of luck unless you're willing to add a headphone jack as I mentioned before. But if you have a cable converter box, or you're using a satellite receiver or other set-top box, you can use your headphones with those. These devices typically have direct audio and video outputs available on the rear panel, and you can use that audio output to feed the headphone transmitter.

What most people do these days is use a home theater receiver along with the TV. All sources (the cable box, DVD player, video game console, audio CD player, etc.) connect to the receiver, and the receiver's audio and video outputs go to the corresponding input jacks on the TV. This way, the TV is just the end of the line. The receiver also would provide an output for the wireless headphone transmitter. This system offers some advantages. You'll be able to connect the proper speakers to enjoy surround sound when not using headphones. And you'll be able to use your wireless headphones with the tuner and audio sources like music CDs when not watching TV.

From the manual:

1. Plug the stereo audio cable into the headphone jack of your audio
source (e.g., stereo, TV, CD player, DVD, etc.). If your audio source
has two RCA output jacks instead of a headphone jack, use the
supplied Y cable to connect your headphones to the two (red and
white) RCA jacks.
2. Connect the other end of the stereo audio cable to the AUDIO IN
socket at the back of the recharging cradle/transmitter.
3. Connect the AC/DC main power adapter to the DC IN power
supply socket at the back of the recharging cradle/transmitter. Then,
connect the adapter to an electrical outlet.
Important: This power unit is intended to be correctly oriented in a
vertical or floor mount position.


Manual:
http://audiovox2.info/docs/common/AW772/AW772_OM.pdf

I had the same problem with Brookstone wireless headset the only solution I found was plug in the red and white connectors to your cable box it works perfectly that way. Just make sure the red cable connector from the transmitter is connected to right red input connector on the box. I have a Comcast cable box. Now I need a solution for them on my PS3?