The issue here is that the Voice VLAN OUI MAC table is pre-populated with phone OUI MAC addresses. Those are implemented with ACL's and on the 19x0 switches is limited.
Please take a look at the Voice OUI MAC table and remove OUI's for products that you do not have on your switch. You can do this with the WEB GUI on the 19x0 switches. It is under the Network navigation choice on the left. You can display what is defined, and add or remove them as needed. Those choices are in the top navigation menu bar.
As an FYI, for other more featured switches, you can do this in the CLI:
Use the display voice-vlan mac-address command to view it. For example, this is what I see on a 4-slot 5930 switch:
<5930-4-slot-JH179A>disp voice-vlan mac-address
OUI Address Mask Description
0001-e300-0000 ffff-ff00-0000 Siemens phone
0003-6b00-0000 ffff-ff00-0000 Cisco phone
0004-0d00-0000 ffff-ff00-0000 Avaya phone
000f-e200-0000 ffff-ff00-0000 H3C Aolynk phone
0060-b900-0000 ffff-ff00-0000 Philips/NEC phone
00d0-1e00-0000 ffff-ff00-0000 Pingtel phone
00e0-7500-0000 ffff-ff00-0000 Polycom phone
00e0-bb00-0000 ffff-ff00-0000 3Com phone
On the 1920, you may have a few less than this.
To remove one, use the undo voice-vlan mac-address command in the System CLI. If you need to add one, don't say "undo." On the 19x0 switches, this is all done in the WEB GUI as I said above.
Once you have removed the ones you don't need, you should be able to apply the voice vlan to all of the ports.
Regards,
David