Samsung VoIP handsets completly lockup

[Talligen]

Hey everyone, I was hoping someone might help me troubleshoot this problem. I've inherited this problem from another admin who was at his wit's end trying to figure it out.

We've got a Samsung iDCS 500 PBX connected to 7 ITP5121D VoIP handsets. Some of the handsets are at another building (the two buildings are connected via fiber). There are no VLAN's.

Everything was working fine for the past year up till a couple of months ago.

Now, all of a sudden, the handsets lockup all at once (almost on a daily basis but at different times during the day or night). By lockup, I mean if a call is in progress, it is dropped, the display on the handset freezes (the second (blinking indicator stops blinking, the VM light stops blinking (if the user has VM)).

Has anyone ever heard of anything like this before? Where should I begin troubleshooting this issue?

 

[Talligen]

So, it just occured to me...maybe there's a licensing issue?

Here's my hypothesis:

The handsets are trying to find a license but the license is expired. Not being able to find a valid license, they all lock up at the same time. OR perhaps the opposite is occuring. The PBX checks for a valid license. Not finding one, it sends a lockout signal to all connected handsets.

Can anyone confirm or elaborate on this?

 

[OldAndKnackered]

If it is an iDCS 500, then it isn't a licencing issue. It sounds to me that it could be a bandwidth issue (are the phones using the same network that is having large files transferred or downloaded. You may have to setup QoS to prioritise voice calls. The other possibility is that there is an issue with the MGI card, which is what handles the VoIP.

 

[Talligen]

It is indeed an iDCS-500, with an MGI-16 and an SVMI-8E installed.

The phones are on thier own subnet and there is no DHCP server. They're connected through a mix of 10/100 Cisco 2900XL, 2950, and Netgear FSM7328S managed switches. QoS is not installed.

I'll take a look at the MGI card and reseat it. Is there anything I can check to see if it's causing the problem? Logs, event history, lights?

 

[OldAndKnackered]

If you look in mmc 851 it may give you a rough idea