Hello Larss,

I do not work for RME nor am in any way affiliated with RME, do don't take what I say as 100% fact, but a few users from the GearSlutz forums (at least 2) have mentioned that the ADI-2 Pro requires a bit of burn in time.

For example, on the following thread:

https://www.gearslutz.com/board/masteri … pro-5.html

...user blazp mentioned the following:

"But i made the comparesen from the old ufx. I found the low frequency on the ufx go much lower than Adi 2 pro. The ufx have a nice punch that Adi pro haven't. I use sharp filter wich is default set.
Have someone to have new ufx+ to made a comparesen with Adi 2 pro? What is different in the sound. I want to sold Adi 2 pro and buy a ufx+ but i don't know with sound axpect what is better to listening."

...but then after a bit of usage, mentioned the following:

https://www.gearslutz.com/board/masteri … pro-6.html

"Can someone tell me where and how set headphones 1/2 output to work. Now only work 3/4. Unother questions where set the balanced for main out. If i turn encoder 2 when press the vol button i only change the bass or highs not the balance wich explain in the manual. The bass now is very good. "

RME will likely "officially" claim that there is no burn-in time with the ADI-2 Pro, but given how 3 forum members (so far) from GearSlutz have mentioned that after a burn-in time, the ADI-2 Pro "opened up", I recommend you use it for a few days to a week before returning it (also, try using a slow filter - as that has been claimed to sound more musical).

Nelson