Topic: XLR connector stuck in FF400


I've plugged an XLR microphone cable into input nr 1 on my FF400.
When trying to unplug it i noticed it was stuck. The neutrik push/release
button was no longer there. I found it later on in my backpack where it seems to have
fallen off the unit.

How do I repair this? Do I have to take the thing apart?

Heres a picture with the metal push/release button laying on top;

Thank you for your advice!


Re: XLR connector stuck in FF400

As far as I remember it will not be possible to slide in the metal piece when a XLR conector is inserted. That means a technician has to open the unit, then carefully lift the lock from the back side of the socket so that the XLR connector can be pulled out.

Matthias Carstens

Re: XLR connector stuck in FF400

Thank you for your answer Matthias!

I bought the unit from Musicstore Koeln in aug 2006. They have three years warranty, so that warranty.

I could try to open the thing up, and fix it myself, since the warranty period is over! Right?

However I can't get all the screws to come off, it seems one of them is stuck. And the screw is starting to get a bit torn in the edges from me trying to make it come off.

Is this screw stuck on purpose? To prevent non technicians like me from fooling around?

What should I do now?


Re: XLR connector stuck in FF400

No, it is fixed from corrosion, quite normal. Using a correct screwdriver from the start would have prevented that. You might now be forced to use a drill to drill out that screw.

Did you try to insert the lever from outside? Last time I tried it did not work, but later I wasn't sure I inserted it in the exact right place...

Matthias Carstens

5 (edited by 19 frets 2010-10-13 20:43:34)

Re: XLR connector stuck in FF400

Proceed at your own risk, but I have had this exact same problem with rounded out screw heads.  What you need is a small diameter "screw extractor".  Here is an example. … PartNumber

You need to make sure you get one that is the proper diameter so that you can get a good "bite" on the screw inside the cross section where the phillips head screw driver mates.  Although they are made for an electric drill, I would use a T-handle with it so as to be able to proceed very slowly.  You don't want to strip the head off completly.

And....  no, the screw is not locked in place.  I have sucessfully removed the covers before and all screws are designed to be removed.  They sometimes get torqued too tightly during production, installtion of the rack mounts or repair and over time, they corrode and become very tight.

Good luck if you try it on your own.  I can tell you that it is a jungle in there and things are pretty tight.  I can't remember how accessable the area around the XLR plugs is.  But if you are careful and can get the screws out, it won't hurt to have a glance inside and see what the problem looks like under the covers.  HeadScratch

Re: XLR connector stuck in FF400

Maybe just a drop of WD-40 over the screw and waiting some minutes to break up the corrosion. Or a spray lubricant for plumber.
Well just an idea...

Asus P8Z77-V LE Plus_i7-3770K-3.9GHz_DDR3-16GB_Win8.1-x64_TI FW PCI_1xUAD-2_Cubase 4&7

Re: XLR connector stuck in FF400

I think if you persist in working from outside the box, sliding different thin tools and pressing in different directions, you will eventually free the plug.  Just be sure not to force it, when it's ready to come, it will come easily!

Alternatively, chop the cable and solder on a female XLR.  Inelegant, maybe.  But it should work for years!

8 (edited by JonasAnd 2010-10-15 15:00:22)

Re: XLR connector stuck in FF400

Thank you all for some intelligent advice!

I did manage to twist one of the rack ears so the stuck screw moved a bit, then I
tried with a screwdriver of the correct size and the last screw was off! (I've certainly learnt a
lesson to always use right size driver..)

So now I've open it up and removed the top to get a peek of the back side of the
neutrik XLR jack.

a closer look, photo taken with my crappy mobilephone camera though

I'm not really sure as to what I can do from the back, there is a small hole where I can insert a thin tool but I can't see anything in there, and don't know how the locking mechanism works. I've tried poking around randomly but no luck.

I've also tried to poke something in the front hole where the push button used to sit, but no luck. The hole is so small that there is no chance of steering in any direction.

I've also tried to insert the little metal push lever/button but it is not possible without bending the small metal hook-thing that sticks out from it, possibly destroying it. So I did it anyway! But it seems this tiny bit is a crucial part of the unlocking device, so we have a catch 22. Cant stick it in without taking away the unlocking mechanism.

I like your idea, Laurence Payne, of soldering a female XLR on, as a last resort. Only problem is if I one day want to sell it, it would be harder to get a good price.

What to do now?

Re: XLR connector stuck in FF400

Take it to a repair shop, who will be able to replace the socket properly and neatly.  You aren't equipped to do any more.

10 (edited by JonasAnd 2010-10-17 10:28:42)

Re: XLR connector stuck in FF400

But I have some experience of repairing electronics, tube amplifiers mainly
and I have also built a delay pedal once. So I know how to use a soldering iron.

If I had the exact part number, I think I could pull it off.

Does anyone know the exact neutrik model in the FF400?

It should be one of these; … tlist.aspx



Re: XLR connector stuck in FF400

The sockets we currently use are different to the ones in your unit - they are open at the back, that's why I gave you the above advice. I am pretty sure that you can pull out the XLR as soon as you insert something in the top which does the same as the metal plate. The noses going down are retention stops, not for the XLR lock. IMHO. I will ask tomorrow in the factory how to fix this one.

Matthias Carstens

12 (edited by Laurence Payne 2010-10-18 11:34:35)

Re: XLR connector stuck in FF400

JonasAnd wrote:

But I have some experience of repairing electronics, tube amplifiers mainly
and I have also built a delay pedal once. So I know how to use a soldering iron.

Fair enough!  I based my assessment of your skill level on your report of managing to round off a screw by using the wrong driver :-)

13 (edited by JonasAnd 2010-10-19 21:52:50)

Re: XLR connector stuck in FF400

Matthias I can slide the metal piece in (after bending the pin), but nothing happens, either the pin was part
of the locking mechanism or something else is broke inside, maybe a spring or something.

If you could ask at the factory,  I'd be glad!

I am starting to think that I should replace the XLR socket with a new one (if it is not possible to fix in any other way). But it would be very helpful to know what the exact model is in my unit.

Also it would be nice to know how heat-sensitive the components connected around the XLR socket are and if so if it is possible to use a heatsink (I've never used one before as I've only worked with larger components).

Laurence, I understand what you mean :-)  You are correct I'm a hobbyist repairer and sometimes I do screw up (bad joke I know)..


Re: XLR connector stuck in FF400

I got reply from the factory today. They had this problem now two times and in both cases had to desolder (remove) the XLR socket, and solder in a new one. No way to unlock it. Sorry.

Matthias Carstens

Re: XLR connector stuck in FF400

thanks for your help Matthias!

I've bought a new socket to replace the broken one...

It's a neutrik NCJ6FI-H

3 pole XLR female receptacle with
1/4" stereo jack without switching contact,
horizontal PCB mount

Would that do?

There are different XLR+1/4" combo socket models
from neutrik with different specs;

The 1/4" jack is available in mono,
stereo, stereo-switching and stereo-switching with switching
XLR ground contact...

Does anyone know what stereo switching
and switching XLR ground means? Just want
to make sure I've bought the right socket...

Oh, and sorry for bugging everybody with this problem of mine...I really, really appreciate your help!



Re: XLR connector stuck in FF400

The NCJ6FI-H is the correct model. Stereo (TRS) and non switching.

Matthias Carstens

Re: XLR connector stuck in FF400

I have now replaced the socket!

...everything went well and I tested recording
this morning.

Some comments;

I took the old socket apart afterwards
to learn how the locking mechanism works..
It IS possible to unlock it from the back through
the small hole with a jewelers screwdriver if you know
exactly where and how the lever works.

Best way for anyone having this problem is to actually buy
a new socket just to tear it apart. Start with taking out the
push button (without bending it to much as you will need it later).
then tear the top open with a pair of long nose pliers.
This will get you a good view of the lever so you can
practice opening it from the hole at the back.

After learning this it should be quite easy to unlock the socket on the fireface
and then you won't have to desolder anything.

After the XLR cable is freed you have to install the push button or
it will happen again. If you've lost the original button you can
take the one from the socket you've practiced on.

Anyway thanks for you help everyone!

Kind regards