NRV-10 input gain issue

[marek]

I am using NRV-10 and running firewire driver 1.8.4 on Mac OS X 10.5.6

I am having a very peculiar issue with my gain knobs on my XLR/TRS inputs.

Starting with the gain knob turned all the way counter clockwise, I see nothing on the input monitor as expected. As I start turning the knob clockwise, I can see the input monitor detect some level of signal; however, no sound is output at this time. Once the knob reaches about 95% clockwise, the input monitor jumps up and can finally hear sound, but now the output is all distorted and sounds terrible.

I cannot produce any level of output using the XLR/TRS inputs unless the gain knobs are turned almost completely clockwise.

This issue exists regardless of whether it is connected to my computer with the firewire cable. I've tried restarting the device several times with no success. It seems like a calibration issue. Can someone help?

[Paul]

How long have you had your NRV-10? Has it always done this? Is it doing this on all of the inputs?

[marek]

I just got it yesterday and yes it is doing it on every in XLR/TRS input regardless of whether I'm using XLR or TRS.

When using a mic, I make a constant noise into it as I turn the gain knob up. No sound is generated until the knob is about 95% clockwise and you can hear the sound almost POP in. At that point, the input is being clipped

The FireWire works great. I have my computer outputting sound to reference monitors that are hooked up to the main XLR outputs and they fine. What's up with the other inputs?

[Paul]

This seems like a problem in the gain pots (knobs). I would advise exchanging it with the retailer for a new one.

[marek]

Paul,

I've been reading around the forum for people with similar issues: This seems awfully close to my scenario.

http://forums.m-audio.com/showthread.php?t=2684

Is this a typical problem for NRV-10? It may not be fair to ask this but should I be looking at getting a different mixer?

[Paul]

Some of those posts are about low input signal and 1 was possibly similar to yours. What makes me think this is a hardware problem is that the NRV-10 does this when it is not even connected to the computer. What I usually encounter when looking into a problem where there is no signal at all until the maximum gain (voltage) is applied, is a loose connection or a cold solder joint. Since this happens to ALL of your inputs, I'm thinking the ribbon cable from the analog board is loose. Since it would void the warranty for you to open up the NRV-10 to verify this, I just advise exchanging the NRV-10 for a new one.

[marek]

Well I intend on hooking this up to my computer to use in Logic Pro. Is there going to be a problem if I get another unit?

I bought M-Audio expecting a high-quality product at this price. Please be honest with me.

[Paul]

This is not a common problem at all. I would fully expect a replacement unit to be fine. To be honest with you, I have never seen the ribbon cable come loose on an NRV-10 before, but the symptoms you describe sound like that.

[marek]

hmm ok

I've been tinkering with some things to try to better diagnose the problem.

I hooked up a guitar to a Boss GT-10 multi effects processor pedal. The pedal is a gain stage so it amps the signal going to the TRS input on the NRV-10. If I max the volume on the guitar, the GT-10, and the 45mm fader on the NRV-10 (on the guitars channel), I can start go get output when the gain pot is about 75%.

Does this still sound like faulty wiring to you? Keep in mind, I can see input signal grow FireWire monitor as I turn the gain pot up but no signal is output. The reason I'm pointing that out is the input signal is responsive to the gain pot (even at the lower settings), however, I can't get audible output.

[Paul]

What happens if you push the PreEQ/Post EQ button in?