When you connected the 2960 to the bridge, did you get a link light? You would have to use a crossover cable to connect switch to switch. Perhaps the Dell has an autocrossover port or an uplink port that might have crossed it for you so it worked when you connected it.

Do you have the PC’s connected to the ethernet port on the VoIP phones? If it is being piggy-backed then the ethernet port on the switch that it is connected to has to be a trunk port.

Yes, I would agree that the 802.3q traffic shoulnd’t make a difference in it working or not.

What if you just connect a PC only to the switch and hardcode the VOICE VLAN 10 number on that port, can you ping the call manager?

I think if we can get a some of these questions answered and try some of these tests, we can solve this one

Thanks,
David Davis, CCIE

Personal Website: HappyRouter.com – home of Cisco how-to articles & videos
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