RN102 Slow to access

I'm having a problem with my RN102 - I'm using it to store/stream media on my home network.

My home network is a combination of xp, win7, win8 and win10 machines.

On win 7 I can access the shares and read the folders almost as if it were a local drive.

On win10 its a nightmare - if I click on a drive/share, it'll take ages to give me a listing of the root directory.  I get a green progress bar accross the top of windows explorer that just creeps along at the speed of  a glacier.  I can go away make some coffee, come back, and if I'm lucky I'll be able to see the contents of the drive.  The problem continues if I want to go down a level, read the contents of a folder for example - same thing.

Only from the win10 machine.

Also - I've noticed, if I copy large media files to the RN102, I pretty much can't use it til the next day, because even though the data has left my PC and has been written to the NAS, the drives are working flat out for hours afterwards - I thought it might be to do with the PLEX/TVMobili updating their databases, but surely they can't be needing that much time?

Any ideas would be welcome - the NAS is connected to a switch via cat5 cable.  So throughput shouldn't be an issue.

Thanks in advance