When recording or playback with qu-drive, access to USB key generates noise in the headphone (each time the led lits, there is a sound in the headphone). What does it come from, is it possible to fix it ?
Probably same as QuDrive/ST3 interference.
In fact it may well be ST3, have you checked?
Thank you for your tip, I just tried out and it didn’t solve the problem.
Noise appears exactly when the led is on.
I’ll guess at same root cause, different symptom then…
I have noticed a similar noise on several Mix outputs of my QU-32 while recording using qu-drive on a thumb drive. And yes, it does look like it coincides with the flickering record light near the thumb drive connection. It’s a slight fluttering noise, almost a ticking but not quite a tick. I had just filed a support ticket before I saw this post.
@[XAP]Bob : you were right, I tried again and it’s OK.
First time, I only plugged in ST3 a cable with a passive DI at the other end, the noise was still there.
Then, I plugged a cable with a MP3 player : no more noise 
(I’ll try a stereo plug with tip and ring connected to sleeve)
Thanks,
Hmm, isn’t turning down ST3 volume or muting sufficient? Assigning ST3 input to dSnake or QuDrive should also cure that symptom.
@Andreas : You’re right, as was [XAP]Bob in his first reply. I didn’t check that ST3 was on, with fader at 0dB. With fader down, no more noise. Sorry to bother you with a pb already known. I hope it will help other users.
(Really pleased to have this Qu-16, but I have to get used to it…)