Sennheiser CX 400 Headphones - Page 4 - Answered Questions & Fixed issues

Provide the model number of your Sennheiser Headphone please. Without it, it is not possible to place a solution to this problem. Provide the details to me by Fixya. OK.

Sennheiser Audio... | Answered on Mar 30, 2011 | 281 views


Often the rubber button is pushed into the microphone.
You can easily disasemble the unit.
Just open the batterycase, you will find some small torx screws.


Sennheiser Audio... | Answered on Mar 22, 2011 | 880 views

probably ..they discharged to the max..and this way the connection was reset...If they are still functional have to pair them again with the transmitter... and will work again ...If they work ..avoid in the future to discharge them totally ...
To pair they usually have a button that have to be pressed and will blink until picks up the signal ..or take a look in the manual to see the exact procedure for this model ..

Sennheiser Audio... | Answered on Mar 21, 2011 | 391 views

If you fancy DIY have a look at my tip on headphones, just click my user name to find it.

Sennheiser Audio... | Answered on Mar 19, 2011 | 1,743 views

Sennheiser normally have a 2 year warranty on their products.
You can check your specific model at their website - navigate to the model number and click on download user instructions pdf (top right of page)

Sennheiser Audio... | Answered on Feb 23, 2011 | 270 views

It appears that the 238 has a cable connected to one headphone only.
If this is the case, try your existing cable.
If both ends look identical and plug into your music player easily, you could try any audio cable with
3.5mm mini plugs on each end.

I have used such to drive low powered speakers, and discount the hype about audio cables.

If you look on eBay, entering "sennheiser hd cable", a number of sellers have cables, none specifically claimed to fit.
The cheapest among the first few entries advising the cable has a 3.5mm plug at one end and a 2.5 mm plug at the other. If my first suggestion is unworkable, this will probably work.

Alternatively you could try to find one locally, to test for fit before purchase.

Check the other sellers for a look at pictures and possibly details if I got it wrong at the start and your cable has 2 connectors at one end.

If all else fails, take your headphones to you local electronics supplier, get plugs that fit and get a good friend with a soldering iron to make you up a cable.

Sennheiser Audio... | Answered on Feb 03, 2011 | 450 views

One is for left, one for right, and one for ground...the usual color code is right=red, left=white, and ground = bare wire(or some other color)

Sennheiser Audio... | Answered on Jan 08, 2011 | 1,681 views

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

Sennheiser Audio... | Answered on Jan 04, 2011 | 889 views

it is not as long as the headphones are supported properly.

Sennheiser Audio... | Answered on Dec 30, 2010 | 220 views

When a manufacturing defect is present the unit always fails in the first weeks of use. This is your case, and because it's still in the warranty you should return it and have it replaced.

Sennheiser Audio... | Answered on Dec 03, 2010 | 181 views

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.

Sennheiser Audio... | Answered on Oct 20, 2010 | 1,303 views

First of all if the right side is working the wireless is working alright and the fault is in the processing section, the left audio preamplifier , the left side power amplifier and the left side earpiece.

So you might have to test with a audio signal to confirm from the preamplifier, the low-power amplifier driver for the earpiece and the earpiece.
Once this is confirmed the focus can be the wireless section, possible fault in the receiving section.
The use a a multimeter to check and knowledge of electronic circuits is necessary to check around this section. Please check and respond.

The advice/tip given is with the belief that you are competent. You must attempt to do it yourself only if you are technically/logically able, especially when dealing with delicate devices, damaging while trying to open, Probing electrical/electronic circuits with high voltage or delicate components. Since the advice given by me is with the inputs provided and not based on a visual inspection, there can be further reviews required in some cases.

Sennheiser Audio... | Answered on Oct 27, 2010 | 1,251 views

There is a small arrow on the plastic. Rotate the ear pad counter clockwise.

Sennheiser Audio... | Answered on Apr 05, 2010 | 1,382 views


You're local Sennheiser dealer can fix it, no problem.
The repair takes a half an hour.


Sennheiser Audio... | Answered on Mar 04, 2010 | 2,077 views

You should be able to get a new plug from an electronics store. When you have got it cut off the old one. Carefully remove the insulation from the end of the cable to reveal the wires. There will be two coloured wires and two earth wires. With a stanley knife open up the old plug. This will show you where the wires go on your new plug. You will have to solder them on to the new plug. If for some reason you can't work out which of the two coloured wires go on which terminal. Then you will have to try to identify by sound the right and left channels. The earths go together on the largest metal tag.

Sennheiser Audio... | Answered on Jan 15, 2010 | 750 views

push it in!!! or is it the wrong size?? should be 3.5mm

Sennheiser Audio... | Answered on Sep 02, 2009 | 121 views

Add a DI box to clean up/boost the signal of that mic. If all the channels are doing this, get a bigger (more watts) amp so that you have more headroom.

Sennheiser Audio... | Answered on Aug 26, 2009 | 397 views

I don't know if this is what you want but the link is

Sennheiser Audio... | Answered on May 30, 2009 | 444 views

Check the 1/4' stereo phone plug for broken wires if you can unscrew the shield. If that is not the problem, you will need to replace the plug and the cable up to the left can. I say left because there is another cable from the top of the left can to the right can carrying the right signal. You said left was mostly cutting out so that connecting cable is likely fine. Slip the foam ear pad off the left can and see if there are screws holding the speaker plate to the cup. Inside of the cup there should be a place where the main cord meets up with the other cord. Make note of the connections and the colors of the wires. You should be able to save the cable grommet by cutting the cable close to it and pulling the wiring out of the insulator and then peeling the insulator tubing out. The rest is parts, soldering and careful, patient work. Remember to solder in a ventilated area.

Sennheiser Audio... | Answered on May 13, 2009 | 510 views

Sounds like the beginnings of a rubbing voice coil in your MX160. Verify this by trying another set of headphones on your amplifier/MP3 player/etc. If the "scratching" sound disappears then your music source is not the fault. PLEASE REMEMBER...never turn music source volumes up past 60-65% (think of 1:00-1:30 on a clock face). If these setting are not loud enough, use a booster or move up to a unit with more audio output power. On a larger scale...How did I blow my 100 watt speakers with a 50 watt amp? It's easy....clip (overdrive) your amp....Glen

Sennheiser Audio... | Answered on Apr 07, 2009 | 146 views

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