VERY INTERSTING POINT (!). I have indeed an old Epson printer, whhich is proably the only device in the 2.4Ghz band of my TP Link router, which gives out 5ghz and 2.4ghz (for the slower devices) at the same time.I didn't see anything about it in this thread but I wonder if some of the issues people are having might be due to the fact that USB 3.x can interfere with wireless devices using the 2.4GHz band.
Do you think it would help to turnoff the 2.4ghz in my router completly or would it be enough to turn off the device(s), which are using 2-ghz band. Very interesting point and I hope some peoöle can dive into it, thanks (!)