New Recordings on Remote WMC not grouped by Title

[Mark2457]

I just built a new HTPC for the living room (v8.1) and moved the old one (v7) to the master bedroom. All existing series recordings are still on one in master Bed and I added it's recorded TV share to the media library. Everything works, except one annoying thing. I prefer my recording grouped by title. All the recordings that were on the share are grouped correctly, but any new ones are not. for example

The mentalist is recorded on WMC 7, there are 4 episodes from a few weeks ago and they all appear under "The mentalist" on both PC's
A new episode is recorded this week on v7, it shows up fie in "The Mentalist" folder on v7 (where it was recorded)
on W8.1 it shows up as The_Mentalist_WBBM_2013_11-24 (or something like that) and is not grouped with the others.

It seems the remote machine is not getting the metadata correctly.

Anyone got any ideas of what the problem may be or how to get the remote machine to reparse the metadata (without moving files in and out of folders, as the machines ordinarily have no mouse and keyboard, RDCing kills the WMC session and I have to reboot to get it back, and there's no way my wife will do any of that anyway)

Regards

mark