i have an ac87u for some time, and it has working flawlessy. I use both usb port with harddives connected, streaming to my Apple tv 4k. Got an 2tb and 4tb disk connected. Recently bought an 6tb and copying all my 4K movies over. But they all kept buffering constantly when playing through my Apple TV. Guessed it was to big, and then reconnected my 4tb and now I got the exactly same problem. Won’t play any 4K movies without constantly buffering every few seconds. And they worked perfectly...
Rt-ac87u problems with buffering samba server
Rt-ac87u problems with buffering samba server