T28P phone - Vlan & LLDP dhcp option

[toxicfusion]

Hello,

I'm having difficulty getting a handful of Yealink T28P phones to work with automatically obtaining an IP address using DHCP Option 132.

I've configured router & switches.. Option 132 works 100% perfect on Grandstream phones I have. The phone will power on, and automatically switch to the voice VLAN.

However, the Yealink T28P phones when powered on, Will be stuck on "Obtaining IP address" and never goes to the voice VLAN.

If i manually set the VLAN option within phone network settings, phone reboots and works fine. Any idea?

Firmware: 2.7