Was the FireWire return engaged?

I'll try that and let you know but I'll need to look it up. I don't know how to verify that. Is there a reset capability as well?

Try this:

http://support.presonus.com/entries/213 ... leshooting

Plug a set of headphones into the insert jack for that channel... If you hear the noise (it would only be on one side of the headphones) then a preamp has gone bad... Other than that I suspect the 100 mfd / 6.2 volt cap at the input of the A_D for that channel has gone bad... not a repair for DIY unless you are adept at electronic repair.

I have a 24.4.2 that has very loud white noise on channels 17 and 18 with nothing plugged in. Channels 9 and 10 also have white noise only not as loud. Factory reset did not change anything,
Last night I replaced 35 caps(100uF 6.3V)on the ADC board, that did not change anything. Noise is the same. Going to try and track it down.
I ordered some 33079, PCM 4204 and PCM 4104 chips.
Anyone else have this problem ? What was the fix?

Presonus won't make service manuals available and they won't sell me the ADC DAC boards
But they will let me ship it to them for repair..... that is so messed up. I realize these mixers are designed to go from the consumer to the scrap yard but if I want to spend my money to buy parts for a repair they should sell them. I want to replace the ADC/ DAC boards
I have been a Presonus customer for a long time but that is about to change

It makes no sense to not sell me the parts I need. bleep??????

One phone call to support was on hold for almost an hour then I get ... sorry, we can't sell you those parts.
Yes I'm pissed

Why not buy a second hand SL 2442 for spare parts...? One tip: Also have a look at the fader banks. The DSP board does not neccessarily need to have a failure, but the old faders get dirty over the years...

End of irony.

I don't know how it is handled in your country, but in Europe it is forbidden to use any electronic equipment that was not repaired or serviced by an authorized service company (authorized by the manufacturer). Additionally here in Germany we have to yearly renew a licence, which by a documented test proves the perfect electric state of each piece of electronic equipment used in a public surrounding (like concerts). Modifications of electronic equipment are anyway strictly forbidden.

Don't blame PreSonus for not selling you parts. Nobody does that and there are good reasons for it!

Yes I'm sure they have they're reasons
I have tracked the noise down. All the inputs and outputs of the 33079 quad op amps on the ADC board are passing a nice clean signal from the preamps
When we get to the 33079s on the DAC board, output pins are outputting the white noise along with the signal I have feeding one of the noisy channels
Definitely getting close
I hope this is it and not the PCM 4104

wahlerstudios wroteI don't know how it is handled in your country, but in Europe it is forbidden to use any electronic equipment that was not repaired or serviced by an authorized service company (authorized by the manufacturer).

Perhaps in germany, but not generally in the EC.

I think that it is European standard that any altered equipment/machine/tool/car may not be used any longer (at least in public private use). Also in Sweden no insurance will pay anything if somebody gets hurt or a fire is caused by equipment, which was changed or modified - and it doesn't matter WHO has done the modification. One needs to apply for a new official allowance to use modified (not repaired!) equipment. This is like releasing a new product, so it does not make any sense.

Hey sorry to bump this old thread but did anyone ever find out what component is failed to cause the white noise?

I have a 16.4.2 and chan 3-4 is bad, just white noise with nothing, replaced the PSU on the board already (other one failed)

The headphones in the insert gave no signal or noise at all.

Did anyone find out the problem to this? I'm experiencing the same thing except from channels 9-16. This is pretty devastating. I have nothing plugged into those channels, but I can't help but think that it's not good for them to be in this state. Anyone have any ideas how to correct this problem? It seems like a firmware or software bug within the mixer itself.

The only recommendation can be to open a ticket with Support. Go to your PreSonus account and find "Support" in the upper menue. The yellow button "Create A Ticket" beneath is waiting for you...