The UC320W only has 2 VLAN’s. VLAN 1 is the data VLAN and is untagged. VLAN 100 is the voice VLAN and is tagged. If you are connecting the UC320W to your RV220W you need to make sure that the RV has both VLAN 1 and VLAN 100 configured on it. On the RV220W configure the port for 1 untagged and 100 tagged. You can still configure the UC320W for a voice only deployment. This should resolve the issues you are seeing.
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