[tranhieu]

I have my M3 fed by the udac, and whenever I crank up the udac's volume pass 6 o'clock, popping and buzzing appear where the cans get loud. If I turn down udac's pot and pump up the M3 to get the same loudness level those blemishes are gone. This happened to all of my phones
At first I guess it was the volume pot that played up as I thought we already bypassed udac's internal amp by using the rca out but the phenomenon is just exactly what's described about clipping so I'm wondering...
Or did I simply get a broken unit?

 

[Head Injury]

The uDAC doesn't even go to 6 o'clock. It's off at 7, and maxed at 5. Do you mean noon, or half volume?
 
Your unit may be defective. I've heard stories of people getting channel imbalance at low volume and clipping at high volume (past 3 or 4 o'clock), so I keep mine at noon to be safe. I've never had any of those problems even when I had it low when driving headphones or high when I was first feeding my amp.

 

[tranhieu]

Hehe, I often leave the udac with the headphones sign upside down so that explains the confusion here
Yes, it's half noon if I put it the other way
3 or 4 would be too high, I already get that 'clipping' thing the moment I pass half of the pot
So that is clipping right? I've always wanted to experience it in person