Question about Netgear Nighthawk M5

I use it as a continuous internet network for the house. It is best to remove the battery if you leave it plugged into an electrical outlet.
I bought it as soon as it came out and so far I have only had two problems with connections (rebooting).

Hoi Zäme - for me, the part (battery is out) overheats on USB after 3-4 hours with little to no traffic - what could be the cause?

I use it 24/7, it runs perfectly and I have never had any problems with it.