2830 - can't access or PING devices

Hi,<br/>
<br/>
A customer has a Draytek 2830n which has dual WAN in use and have VoIP phones connected on the LAN.<br/>
When we connect using the '<I>Dial-In</I>' VPN I can't access the web gui of the phone by typing into a web browser or even PING the phone.<br/>
However, using the PING diagnosis from the router does respond to the PINGs but not from my connected PC.<br/>
<br/>
We have other Drayteks, mainly 2860's, which we are able to access the phone's GUI and PING the device so I'm thinking there is something different about the 2830's?<br/>
<br/>
Has anybody had this issue before? <br/>
<br/>
Regards,<br/>
Alan.