Reply to Weird problem with Traktor + DJM 900 Nexus (using mixer's internal card)

Hi,

Last saturday I experienced a really confusing problem. I hooked up my Macbook Pro running Traktor 2.6.3 via USB to the Pioneer DJM-900 Nexus, using the mixer's built in soundcard, and using Traktor in external mixing mode.
Everything was configured as I'd done and used successfully the week before, at another club that has the same mixer model.

At first the 2 channels on the mixer that I assigned to Traktor's A and B decks worked perfectly, and continued to do so for at least 20 minutes into my set.

All of a sudden, there was a very strange mixup: Volume faders for each mixer channel kept working fine for the Traktor deck that was assigned to them, BUT somehow, the EQ controls (lows, mids and highs) for deck B transferred to mixer channel 3, which I had assigned to Deck A. Thus, both deck's EQ controls became assigned to a single channel's EQ knobs . For example:

BEFORE PROBLEM:
Traktor Deck A (assigned to Mixer Channel 3)
Deck Volume = Mixer channel 3 Fader OK
Deck EQ = Mixer Channel 3 EQ knobs OK

Traktor Deck B (assigned to Mixer Channel 4)
Deck Volume = Mixer channel 4 Fader OK
Deck EQ = Mixer Channel 4 EQ knobs OK

AFTER PROBLEM
Traktor Deck A (assigned to Mixer Channel 3)
Deck Volume = Mixer channel 3 Fader OK
Deck EQ = Mixer Channel 3 EQ knobs OK

Traktor Deck B (assigned to Mixer Channel 4)
Deck Volume = Mixer channel 4 Fader OK
Deck EQ = Mixer Channel 3 EQ knobs FAIL

Thus, both of the mixer's channel faders worked fine and controlled the volume level of the deck that was assigned to them, but BOTH Traktor decks' EQ levels became assigned to a single mixer channel's EQ knobs. Needles to say, mixing was impossible. Thankfully, the next dj stepped in using CDJ's hooked up to channels 1 and 2.

I checked my Traktor's preferences and everything seemed to be in order. The only thing that comes to mind is asking the club owner for permission to upgrade the DJM-900's firmware, but I somehow doubt that a simple firmware upgrade will correct such a huge functionality fault.

Any ideas from community members?

Thanks,

Diego