Roon air wifi connection problem

[baddog]

I already bought an asus rt ac88u monster router and paid a lot of money. Overall wireless performance at home increased.  Unfortunetly no big change in dbm for devialet. Should I say that the wireless connection of devialet is sh.t and I will never ever reach under -30 db or should I make some changes in settings

If it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck.

Sadly I think you are finding a limitation in the Premier. It's unfortunate that Devialet support has not been able to provide a recommendation to resolve the issue. I don't think there is a great solution short of the more expensive one of upgrading the unit such that the WIFI capabilities are improved and you gain an ethernet port.