Troubleshooting with HeadphoneVol on DDJ-400

Hey everybody :)

I bought a DDJ-400 in April 2022 and from the beginnig of using it i got a strange problem.

I'm streaming on twitch and after a while ( sometimes it takes 5 min ... sometimes 2 hours ) the headphone volumen gets so low that it isn't nearly possible to hear anything. If i try to set the volume for the headphones it will only work in the first 10% of the vol-control for the Headphones . After the 10% there is no change of volume.

I also realise that everytime i got this trouble the 6th Pad ( 2nd in the 2nd line )  on each player started to blink. but i cant switch it off . On this Pad i got no effect / cue / loop or anything else .

I also tried to change the usb port between usb 2.0 / 3.0 / USB C directly on my PC or into an active USB Hub to check if there are any  Power Suply issues but it didn't change anything .

At the moment i have to pluf out the USB to reset / reconnect the Player to my PC but this will interrupt the Music in my stream :(

Are there any other ideas what to do to fix the problem or is it a kind of Dead on arival ?

Thanks , Stefan