Mbox 2 Pro, distorted output signal
 

Hi!

I'm having trouble with a recently bought Mbox 2 Pro. Unpacked it today.

Even when it's not connected to my PC (used standalone), I get distorted / crackling sound from the outputs (Mon Out, Line Out 1-4, Headphones A & B, have not tested Line Out 5-6). It's not a distorted signal all over the frequency range, but I am hearing quite a lot of pops an crackles mixed with the signal.

I've used different input sources, all of them giving the same result:

* Keyboard, TS jacks connected to DI inputs
* AKG C414, Shure 58, connected to XLR inputs
* Sony MP3 player, connected to DI inputs

The Input Peak LEDs indicates good signal. The amount of distortion is not affected by the amount of gain (at least not until the signal peaks high). I've also tried using the pad switches.

I've tested my monitors, cables, input sources etc. with an Echo AudioFire 8, everything works perfectly.

Any ideas? Faulty hardware? Contact Technical Support for an RA?

Best regards,

Espen

Re: Mbox 2 Pro, distorted output signal
 

I would try trashing prefs(which fixes lots of odd behavior). What happens if you play the keyboard with the MIX knob turned all the way to DIRECT with Pro Tools NOT open?

Re: Mbox 2 Pro, distorted output signal
 

The Mbox 2 Pro doesn't have a Mix-knob, Mbox 2 has. :-)

I've already tried trashing the prefs, also installed the software on two different computers. Same result. If I use the Mbox as audio output from Windows, this signal gets distorted as well (Windows Media Player etc.).

Therefore I disconnected the Mbox, trying to get a nice and clean signal through it when used standalone as an analog mic/signal preamp, without possibility for having Firewire and/or Windows-issues.

So far, I'm stuck.

Re: Mbox 2 Pro, distorted output signal
 

Possible things to check:

Firewire connection issues - what are your system specs?
Or, firewire cable problems.

Another prob could be issues with the converters.

Best you post your system specs!

Re: Mbox 2 Pro, distorted output signal
 

How can system specs or firewire cable be an issue when the Mbox 2 Pro is no longer connected to the computer? :-)

First I had it connected to my computer. Got pops and crackles, even in Windows (Windows sounds / Windows Media Player). Then I thought I should try sending a signal straight through the Mbox, isolated from the computer, therefore I disconnected the firewire cable.

Currently, DC Power is connected (included from Digidesign), monitors are connected, and an input source is connected for testing purpose. Still, I get (the same kind of) pops and crackles. That's why I'm about to conclude with faulty hardware.


Anyway, here is my system specs:

Asus P5K-Premium Motherboard
Intel Core 2 Duo E6600 2.4 GHz
4GB Corsair DDR2 PC2-6400 RAM
Geforce 9500 GT GPU
Onboard OHCI compliant firewire chipset
Western Digital Raptor 73,4GB System drive
Western Digital Raptor 150GB Audio drive
Seagate 1TB storage drive
Samsung 2x500GB (Raid 0) storage drive


I haven't purchased a "Digidesign qualified Firewire card" yet, since my onboard FW chipset works perfectly with an Echo AudioFire 8. But for now I'm not too concerned about this.

Re: Mbox 2 Pro, distorted output signal
 

This definitely sounds like it's defective. You should contact tech support by phone for information on getting it serviced.

Re: Mbox 2 Pro, distorted output signal
 

BTW, Pretty sure you should only use the wall wart supply IF the Mbox 2 PRO is connected to the tiny 4 pin firewire port. The 6 pin port carries power(don't power from BOTH a 6 pin port AND the wall wart)

Re: Mbox 2 Pro, distorted output signal
 

Ok!

I thank you all for quick answers and trying to help me out. :-) I will contact tech support.

Albee: Just for reference regarding your last post. The Mbox Pro 2 Setup Guide states that "Though external power is not always required, you should use external power if your 1394 bus is unable to provide enough power, or if you need to conserve battery power in a portable computer. ... The Mbox 2 Pro can be powered solely through its 1394 connection to your computer, or using an external power supply".

So I reckon you cannot damage the Mbox by having both DC Power and a 6-pin firewire connection at the same time. Probably, when DC Power is connected, no power is drawn from the firewire cable. :-)

Re: Mbox 2 Pro, distorted output signal
 

I need some help. Struggling to post a new thread so hoping someone sees this and can help.

I am new to Pro Tools. Initially had Pro Tools 8.0.1 running on a Mac G5 into a Digi 003. Everything was working fine, but I learned that in order to run a lot of the software I need to run the OS wouldn't work and the computer processors were antiquated.

I purchased a Mac Pro and downloaded PT 8.0.4 and set everything back up. I am finding that PT is "unexpectedly quitting" sometimes and I have a signal distortion in all of the interfaces channels. Still works fine on the Mac G5.

Wondering if it might be a bad firewire card? I could use some help. Thanks! Justin.