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FIX: Neumann KMS 105

Inconsistent audio signal from your KMS105? The fix might be really simple. Here’s how I fixed one.

My wife Katie Nelson and I both use Neumann KMS 105 condenser microphones for live performance. We love how the microphones sound and trust the Neumann brand.

The Problem

Recently Katie’s microphone was passing audio inconsistently. Sometimes it was normal, sometimes the output volume was quieter, and sometimes it would crackle as if the XLR cable was bad.

I called Sennheiser, the parent company of Neumann, to inquire about repairs. They connected me directly with a bench technician who kindly asked questions about the symptoms and then walked me through the fix. He correctly suspected that the hex screws holding the capsule to the internal printed circuit board (PCB) were loose. In fact, the capsule was completely disconnected from the PCB. I was surprised that the microphone worked at all considering there was almost no contact between the capsule and PCB.

PRO TIP: Microphones work best when the capsule is physically connected. #signalflow

The Fix

  1. Take out the machine screw on the side of the microphone that holds the XLR insert in place. There may be a small lock washer underneath the screw. Set them aside.
  2. Unscrew the basket (or grille, as people often refer to it).
  3. Slide off the black capsule cover screen.
  4. Very carefully pull on the capsule while simultaneously pushing on the XLR insert. WARNING: BE VERY CAREFUL WITH THIS STEP. THE PCB HAS A SERIES OF WAVY CUTS IN IT. TOO MUCH PUSHING OR PULLING CAN BREAK THE PCB. GO SLOW. GO EASY.
  5. Pull back the rubber ring around the brass capsule body. Remember the orientation of the ring in reference to the notch in the body.
  6. Confirm that spring is seated properly on the capsule center pin.
  7. Push the capsule body onto the PCB until fully seated. The hex screws should be positioned over the solder-tinned holes.
  8. While holding the capsule and PCB together in that position, use a 0.035″ (0.89mm) hex key to tighten down the tiny set screws.
  9. Replace the rubber ring. Make sure the orientation of the ring fits into the notch in the body.
  10. Carefully insert the assembly back into the body. Again, be very careful. You will likely need small pliers/grips/etc. to pull the XLR insert all the way into position while simultaneously pushing the capsule into the body.
  11. Tighten the screw through the body into the XLR insert.
  12. Slide the capsule cover screen onto the capsule.
  13. Screw the basket onto the body.
  14. Test the microphone. If you still are experiencing audio problems, contact Sennheiser for service.
Little parts are easy to break. Be especially careful with this section.
Affiliate Links

Disclaimer: The links to the hex key and microphone above are Amazon affiliate codes. By clicking through and purchasing, I receive a small kick back. Thank you for your support.



  1. 1 Zeljko Brodaric Jappa 7:53 am Feb 4, 2019

    Dear Mr Troyer, let me thank you very much for your detailed instructions for solving the same problems with my KMS 105 i.e. it had recently started to output an inconsistent signal. I had tested it by recording through it a 1 kHz sine for couple of hours and the recording showed an occasional abrubt as well as periodically gradual changes of level of considerable +- 15 db. Upon tightening the culprit screws (they had been completely loose!) I passed the mic though the same test and had a couple of hours of a consistent signal level recording! Fantastic! You saved me a lot of trouble having in mind that I live in Split, Croatia and that the nearest Neumann service is not around the corner! Thank you again!!!

  2. 2 Scott Troyer 8:01 am Feb 4, 2019

    Fantastic! So happy this helped you. Thanks for sharing your story.

  3. 3 Phil Miller 8:23 pm May 31, 2019

    Absolutely perfect. I had the same problem and didn’t see the allen screws at first. I couldn’t figure out how the board could get a solid connection. The screws were completely loose. THANK YOU so much.

  4. 4 Andy Le Vien 5:04 am Jun 1, 2019

    Would a drop of Loctite be ok on those Allen screws?

  5. 5 Scott Troyer 12:31 pm Jun 19, 2019

    Andy, I’m sure Sennheiser would frown on that, but it would probably work just fine.

  6. 6 Dan 9:23 pm May 17, 2020

    Mr Scott Troyer,
    Thank you so much for such a detail instruction on fixing this problem. I have a Neumann KMS 104 which I love so much had exactly the same problem.I thought i was going to spend another $699.00 on a new microphone until i came across your web site. Your instructions were so precise, had no problem fixing the problem and the microphone is working like a charm. Once again, thank you sir. May god bless you.

  7. 7 Scott Troyer 1:11 pm May 18, 2020

    Dan, it is always great to know that something I’ve posted has helped someone. Happy to hear you had success!

  8. 8 Gary 11:24 pm Sep 11, 2020

    Thanks for the awesome tutorial! My KMS105 recently started popping and produces a static sound. Then, it’ll work great and without warning, start popping again. I opened the mic as showed and found the set screws. I’ve got hundreds of hex wrenches and not one was small enough so I don’t know if that’s the issue or not. Will prob order a .89mm and try again but I’m not convinced I’m having the same issue your wife had. Your thoughts?

  9. 9 Tyler Erik 11:45 am Oct 22, 2021

    Thanks for the thorough write up, Scott! I’d been struggling with this issue for sooo long…I finally took the mic apart last night to find this same exact issue…I so wish I would have found this article way sooner!!!
    Anyway, surprisingly after making the fix, the mic has a very annoying (slight) high frequency feedback issue that it didn’t have before…maybe the lack of ground was acting as a kind of compressor for that issue before…haha. This is what led me to start really Googling. Always something!

  10. 10 Scott Troyer 12:28 pm Oct 22, 2021

    Hi Tyler, it’s good to hear that this fix worked for you. I’m not sure what the high frequency noise would be. Good luck!

  11. 11 Ivan 10:03 am Dec 7, 2022

    Hey Scott (and Gary).

    I have basically the same issue as Gary – sudden static noises and crackling, then nothing. I might try your solution and see if it works.

    Gary, have you tried to repair the mic with Scott’s approach?


  12. 12 Jeremy 12:39 pm Apr 22, 2023

    My KMS105 stopped working altogether. When I took it apart, I observed that the connection between the PCB and the XLR end is completely different from your illustrations. The board does not connect to the XLR at all, and there are four wires that appear to have come loose, that look like they were connected to the PCB with a tan substance. I just don’t know what wires are supposed to go where! Any ideas? I’m betting the mic was manhandled by a student at the school where the it lives…

  13. 13 Scott Troyer 12:47 pm Apr 22, 2023

    Jeremy, I’ve sent you an email. If you send pics of the mic, I maybe can help you.

  14. 14 Francesco 2:49 pm May 5, 2023

    Hello Scott, thank you so much for this detailed guide, the only one available online. I have a 105 and have no audio problems at the moment, but the microphone makes a rattle when shaken, as if something is moving inside. What do you think could be causing the rattling? These two screws? Is it worth opening the microphone? Thank you in any case and keep up the good work!

  15. 15 Scott Troyer 8:15 am May 6, 2023

    Hi Francesco, I think it’s definitely worth opening it up to figure out what is rattling. I had a similar problem and it turned out the mic capsule cover screen had broken after the mic had been dropped. It was an easy fix after purchasing a new capsule cover. Full Compass sells replacement capsule covers here: https://www.fullcompass.com/prod/206545-neumann-079039-mic-capsule-cover-screen-for-kms-105

  16. 16 Kirk 11:17 am Dec 24, 2023

    This is the best page on the internet. I had a problem. This came up first on search, and had actual useful information. My faith in humanity is restored

  17. 17 Mr M 5:31 pm Jan 14, 2024

    Wow – I have this problem with KMS 105 also. The two tiny screws were super loose and I could not tighten them with any size screwdriver. I see its a hex 0.035 thanks for this super tip. I had a sudden loud noise through speaker. This problem may have started a year ago I noticed a female singers voice and others seemed to breakup for a second or two. Thanks for this article.

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