I have recently bought the above mentioned router. I attached a brand new Samsung Portable SSD T5 USB 3.1 Gen2 capable of speeds up to 540 MB/s, which i have tested on my linux laptop and got 450 MB/s R/W speeds. The problem is that when i transfer files from my computer to ssd through my router's usb sharing feature via Local FTP access method i get write speeds of 25 Mb/s. My computer's wireless card supports 400+ Mbps rate. I have also test it with my Xiaomi Mi 10 android phone which has transfer rate up to 9 Gbps, the results were the same. Worth to mention that router's cpu/memory load hasn't exeeded 57%/44%. My read speed is 30 Mb/s.  Both devices where exactly next to the router so that is not a signal issue. I have read other threads too here with different routers models -including mine- with the same problem but i found no solution. Is there any workaround or Is this a malfunctioned device?

Thank you in advance.