@ZGWSTORES The exact same thing is happening to me. I have a C5400 that is working extremely well except for this USB problem. It has actually been happening since I bought the router. I really don't...

@MikeD_PA Make sure you have rebooted the modem and, after it has rebooted, then reboot the router. Also, I found that turning off QOS and statistics in the router's settings, and turning on NAT...

@Kevin_Z Thank you very much for the information about the C5400 V2 Kevin. I do have a question (or request if you will) . . . . Since this appears to be a unique situation where the router is...

@Kevin_Z Kevin, Are you saying that the US and EU firmware versions are the exact same for the C5400 V2?? I can install the EU firmware on my US router? I had always thought that the firmware was...

@Kevin_z Kevin - can you please let us know if TP-Link plans on releasing updated firmware for the C5400 v2 United States version?? I am having the same "half-speed gigabit" problem that others are...

@Felix.LL Try the solutions listed in the thread https://community.tp-link.com/us/home/forum/topic/150603.