C24 C|24 Studio LS and Cue outputs low volume level

[gandlz]

Hello,
I just setup a used C24 and it seems to work, but Studio LS and Cue outputs lower the volume coming from 192 IO significantly. Let me explain:

I send 6 channels main and two channels cue to the C24 input directly from 192 IO and send them back to it. The main channels with control room level at 0dB dropped about 2dB when coming back. I think this is alright.

But the Cue output (pot all the way up) dropped about 9dB and the Studio LS dropped about 19dB which seems pretty bad to me.

Can anyone please test this so that I know there is something wrong for sure?

I did the two reset options from utility menu without any changes and checked trim settings manually. I also noticed that the Studio LS also has a trim coming up when holding its ON-button. I can raise 10dB but it has no effect.
Also did the noise floor test but results are OK.
Cue Pot also passes some signal when all the way down. Just for info – no problem to me.
The dropping volume is also noticeable when sending same signal to Main and Cue while listening to headphones and toggling “from Cue”-Button. (Cue pot all the way up)

Thanks for any input!
Gandlz