Topic: RME UFX problem: pulsing noise on analog inputs

Hello! Need your help.

I've just purchased used UFX and there's an annoying problem. One minute after switching on same noise shows up on all analog inputs. Of course, nothing is connected to them. Preamps, digital inputs and all outputs however are totally silent (of course until I send those analog inputs to them ).

It's in a range from -70db to -60db with some spikes up to -45db. If I turn gain to maximum it's possible to hear some random pulses in monitors.

Here are two videos to illustrate what's going on:

https://www.youtube.com/watch?v=j8t5t9Nuvbw

https://www.youtube.com/watch?v=RK3k63Sw2j0

Sometimes it disappear for a minute, but after always get back.

What could be the reason for it? Bad power supply? Problems with grounding and some kind of power problem in my studio? Problems with computer? I connect it via USB to Mac Studio M1.

I should notice as well, I live in old 19th century building and there are some problems with static and some general electricity "anomalies". Also there's no grounding in the building.   

I also have UCX and it works flawlessly.

I'm afraid it would be too difficult to send it directly to RME for diagnostics, so please suggest what can I do here on my side to track the problem and maybe try fixing it myself.

Thank you in advance!

Re: RME UFX problem: pulsing noise on analog inputs

Firmware is updated to 361 ?

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue

3 (edited by tajnost 2023-02-23 03:03:36)

Re: RME UFX problem: pulsing noise on analog inputs

waedi wrote:

Firmware is updated to 361 ?

Yes, I’ve just updated it, still same.

Investigating it further, my rack stand has solid sides and seems like they close ventilation holes on the sides of UFX, maybe this could be an issue?

I’ve removed it from the rack, disconnected everything and now trying to see how it works in standalone mode in a different room and with different power cable.

Re: RME UFX problem: pulsing noise on analog inputs

Is this noise issue also visible on the front display ?
Make a video of it.

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue

5 (edited by tajnost 2023-02-23 03:34:13)

Re: RME UFX problem: pulsing noise on analog inputs

waedi wrote:

Is this noise issue also visible on the front display ?
Make a video of it.

Yes! And it’s also happening when usb cable is unplugged from my mac.

Can upload video, but it looks 100% same as in total mix. Should I do that?

By the way, thank you for troubleshooting!

6 (edited by waedi 2023-02-23 04:23:52)

Re: RME UFX problem: pulsing noise on analog inputs

Yes, please provide a link to that video.

By what you say, I recommend to send an Email to the support :
support@rme-audio.com
including a link to this thread.

And pull out the electric power cable, before it burns !

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue

Re: RME UFX problem: pulsing noise on analog inputs

UPDATE:

Seems like I managed to fix it.

Looks like there's a problem with my power distribution in the studio room or a device in a chain that causes interferences. I've just connected UFX to the different power wall socket and so far all seems good now, - 99db as it should be. No noise at all.

Will investigate it further, but all seems fine for a now.

If you can give some recommendations on how to avoid such things and protect UFX from power interferences, I would appreciate a lot!

Re: RME UFX problem: pulsing noise on analog inputs

Unfortunately was a false fix. Still experiencing those noises on analog inputs, tired it in another room with different laptop and on the next day in a friends studio - still same, the only difference - it starts to appear in approx. 1 - 1.5 hours.

Contacted RME support - they say: "This could indeed be a failing power supply. Unfortunately, that's difficult to confirm without replacing it."

So gonna try to find the way to fix it locally.

In the meantime, do you think this could be caused by dying capacitors in power supply? Maybe it's a good idea just to ask experienced tech to replace them?

Re: RME UFX problem: pulsing noise on analog inputs

2 weeks later UPDATE:

The UFX was in service, technicians replaced all the capacitors on the power board and told everything else looked fine. At first it was an illusion that it helped - about 7 - 10 first hours of UFX worked without notable issues, levels on analog channels were at -94-99db when nothing connected, but after again - strange inconsistent pulses on the first 8 analog inputs jumping around -50db -70db.

Sometimes it fades away to norm but after always gets back again gradually.

Strange that the issue is not visible on preamp / mic inputs 9-12, they are totally silent at -100db all the time.

I managed to make a short audio recording and a video of the issue, here they are:


https://drive.google.com/file/d/15T3JLM … sp=sharing

https://drive.google.com/file/d/13gm3Ic … sp=sharing


Any recommendations what to do in this situation? What could be steps to diagnose this?

10 (edited by waedi 2023-03-09 03:30:18)

Re: RME UFX problem: pulsing noise on analog inputs

Was this service a partner of RME ?
The unit should go to an official service partner.
https://www.rme-audio.de/Supportkontakt.html

M1-Sequoia, Madiface Pro, Digiface USB, Babyface silver and blue

Re: RME UFX problem: pulsing noise on analog inputs

waedi wrote:

Was this service a partner of RME ?
The unit should go to an official service partner.
https://www.rme-audio.de/Supportkontakt.html

Unfortunately no official service partner here, otherwise I wouldn't start the topic.
Sending unit abroad is not the best option, especially at this time.

So I'm trying to figure out what would be the best in this situation.
Probably local technician still can fix it, just want to gather more info and recommendations for him.

I'm aslo in contact with support@rme-audio.com
Hope they will find a way to help.