Hi - hopefully someone has had similar issues!
Recently installed the VR600 to replace an erratic BT Home Hub 5. Big improvement in stability and consistency of speed, BUT ...! My wife has a work laptop that she uses to access her system via a remote desktop. This all worked fine on the BTHH5, but now won't connect to the remote desktop system - connects to internet and goes through the usual connection process for the desktop, but just times out. Her tech support guys reckon it's an MTU issue.
I've had a look in the TP-Link modem system details on-line but can't find MTU details anywhere in the Avanced tab.