Hello Matthias,

great to hear this issue is already known and will be fixed in the next firmware. That's why we love RME!

Ah, OK. You are entirely correct, it's stated in the text, but it is missing in the block diagram "USB Class Compliant Multi-channel mode" (pg.38), the selector isn't present compared to the previous diagram for stereo mode. That's why I overlooked it yesterday, just saw the diagrams and stopped further reading, d'oh :-(

Anyway, I now checked this digital cable loopback routing in multichannel mode**) and the effect of eg the volume control at -6dB is reflected in the output (dithering), and when set to 0dB I now get the expected correct bit-perfect output!

So it seems the output stream of the DSP rendering is correct (and it does auto ref-level "wrap arounds"at the transitions), but the actual feed to the AK4490 is not... I understand it's not so straightforward to debug/fix this.

Big thanks for taking care of the isseu, and I look forward to try the new firmware.

**) ran into a slight problem there, neither Foobar2000 nor Audition ASIO channel selection/mapping to AES output did work. With Foobar I couldn't fix it at all, and with Audition it only worked when I send to analog-1/2 I get a signal at AES and all other output (like it were still 2-channel mode)??

Yes, I'll be glad to beta-test a new FW. I'm on Win7/64 and would need the corresponding FW updater.

BTW, I have a few other topics for future convenience/usability updates, the most important one is an additional "true analog levels" meter screen where the actual voltages (and max I/O voltage ranges) at all physical input/output ports can be monitored, preferably in dBV (who needs/uses those dBu's anyway) and Vpk. This would be helpful, no need to calculate the true levels manually every time a setting is changed. Since the device knows the effective analog gains applied to the individual inputs/outputs at any given moment anyway this should be feasible... will open an extra thread for this...

I know, and that's OK, RMS is not needed anway. Peak levels is what would matter here.

>> Once we fixed this issue we found another one

What bug is/was this one, so we know the difference for testing, while no release notes given.

I know it sounds weird but beta firmware make some minor changes with sonic sinature of adi-2
(i was made update during playing music)
so i decide to go back to official 185/90

"the correct one" where? on the LSB level only? 
I don’t know exactly which part of the signal processing was covered by the reprogramming of the FPGA. Perhaps this is an anti-placebo, but the sound of the beta firmware seemed more "sluggish." And this is despite the fact that before that I had updated the firmware and did not notice any degradation of the sound.

I know about this argument, but the method of blind test with a grueling repetition of one piece of music is completely different from the usual listening experience. With the help of a blind test, you can "prove" the absence of a difference between 24bit lossless and 320 kbs mp3 audio. But this experiment does not mean that there are no differences between them.

Perhaps I am mistaken, but I do not insist on my opinion. This is just an 'first impression' (which is often true). In any case, the blind test involves the serial downloading of the new update, and in such a way that I was not aware of. It's easier for me to stay on the old firmware and wait for the official update.

regarding: FPGA firmware 192 should fix both issues and provide perfectly looking LSB presentations. Note that this is not an official release, that one will come later, together with other goodies.

When will this happen?

Hp