Follow up to recently closed topic - Roon loses network connection

Hello @Lawrence_Klein
I also use this exact router ASUS RT-AC88U for DSLwith Roon - without any problems!
Just another idea:

LTE cell ISP, so do you have an LTE modem?
… LTE is a shared medium, so performance drops and disconnections may occur.
I have a Telekom LTE router as well, besides the Asus, and recently wrote about my experience with Roon via LTE: