Hello dear RME-team & audiophiles,

I purchased an ADI-2 Pro (not FS) recently (used, on ebay) and am very happy with the overall performance.

I use it as a DJ tool to preview/-listen to music (PH 3/4) and play a set (Main 1/2) t the same time.
On my last set I ran into a problem I can't find any information on, please post a link if I missed an existing thread.

What's the problem/error:
Stage 1: The display got turned upside down (and I believe mirrored horizontally as well), still fully functional
Stage 2: The display froze (turned upside down, mixed up a bit), the sound was still playing but since it was frozen, I couldn't see any reaction to the push/turn of any buttons

What happened then:
- I continued my set for about 3 hours with a frozen display, sound worked perfectly with no glitches - except the non-responsive UI
- Afterwards I turned it off (Main Power Button worked) and on again, the UI wouldn't "boot" / start / get past the grey starting screen with no text
--> same after I unplugged the power for about 10seconds
- A few hours later (with no power in between) I could start it up normally and everything seemed fine

What I did since:
- Factory reset
- Update from firmware 0.86 to .088

I did a few test runs and the error (Stage 1) reoccurred. I can't pinpoint on what triggers it but mid-song the UI goes haywire and turns upside down.

I run a Thinkpad x230 on Linux Mint with Mixxx 2.1 (note: a friend runs his ADI-2 pro (non-FS) on Archlinux with Mixxx and it has been working fine for months)
The ADI-2 Pro apparently needs to be set to:
I/O - "Phones Out 3/4" - "Source: USB 3/4" so the preview/-listen function works when I set the Mixxx output to "Channel 3/4"

Questions:
1) Does anyone have any idea what causes this?
2) Hopefully not a dummy-question: Does the maximum sample rate of 768khz have anything to do with the bitrate of the soundfiles I use?
When running the tests back home (after the initial crash) the two times the error reoccurred was when using soundfiles ".aiff or .flac  & >1000 kbps"

All the best
-Aljoscha

P.S. Answers in German and English are both fine.
P.P.S. Is there a way to upload a picture from my Computer (so you can see the UI for yourself)?