NCP1000 IP handsets and Cisco POE switches

[meanmofo]

Hi folks
I have a NCP1000 running 3 sites via VPN with Cisco (customers own) POE switches at the remote sites. The IP handsets together appear to lose power, lockup or reboot completely at random at the two remote sites (not at the same time) the is also issues with one way audio at times.
Panasonic have looked over the programming side which is good and offered me the suggestion that something was attempting to use one of the IP addresses used by the IP handsets.
I have been assured by the customer that this is not the case. (The customter is also the network engineer)
Has anyone had any trouble with Cisco switches and Pana IP handsets?
Any help would be gratefully received
Regards
Davog

 

[obtsystems]

if something is clashing or the phones are being blocked getting to with the second ip address(DSP) of the NCP it will cause one way speech and cause rebooting of the ip sets. try running a ping to the dsp address from remote site when fault is happening

 

[meanmofo]

All the phones are static outside the DCHP range. The VPNs are pretty much open to all traffic between the sites. Portforwding is set up and points to the IP of the PBX for external traffic coming in.
Would the Smart Cisco prevent the jump from .101(PBX) to .102(DSP)

 

[obtsystems]

It is the ip set on the pbx you have to be careful of, there are two, one pbx ip the second one is for the dsp
If you can't ping to the first one. You won't connect to the system with the maintenance tool or the phones will not register. If you can't ping to the second ip on the system, you will get one way speach and rebooting of the ip phones
So you will need to ping these addresses when the problem is happening to see if that is the fault.you will have to test this locally and on the remote site to see if it is a local ip clash or if it is the VPN causing the problem. It could be a faulty dsp card either.