Have two remote locations on subnets 192.168.1.0, and 192.168.2.0 using 2820's VPN'd to a central 2600Plus with a network based on 10.0.0.0
Remote users use Remote desktop to access computers at central site - all works fine as expected

Swapped the 2600 for a 2830n and configured. Firmware upgraded
Model Name : Vigor2830n
Firmware Version : 3.3.7_232201
Build Date/Time : Feb 9 2012 18:12:44

Local and internet connectivity is fine.
VPN's show up in green as connected to remote locations - so far looks good.

But can ping any non-PC device from one subnet to another but cannot ping a PC!
From a remote location can get Remote Desktop login screen for a server but not a desktop.
Swap back to the 2600 - all works as expected.

Can someone point me to the what is different with the 2830 and any configuration options I might be missing or misunderstanding.
I've spent the best part of a today trying to work out what is going on, but it's all a bit of a mystery.

I am sure there is a firmware available from support which helps the 2830 on VPN issues. Please raise a ticket.