Audio 4 and phonic digitrak recording issue

[MoMo92]

Hi guys, recently gone onto DVS using an audio 4 from a mate, and I've tried to record mixes using a Phonic Digitrak connected to the record out on my mixer. Only when I listen back to the recording I have a high pitched whine/hum throughout the recording, more noticeable in breaks etc.

Is this because I have 2 usb audio interfaces connected to the computer? If so is there a way around it?

Cheers

[Patch]

Sounds like the timecode signal making it through to the rec out...?

[MoMo92]

I thought that was it too but took the needles off and just played internally and theres still the sound.