IOS dhcp and polycom 501 phone

Anyone familiar with any issues with this setup?

We're having intermittent success with these phones successfully completing the dhcp process. The router shows the addresses as bound but, the phone never reboots/initializes with the address and the address is unpingable.

Also seeing conflicts immediately after pool clearing or router reboot

1721#sh ip dhcp conflict IP address Detection method Detection time VRF x.x.x.211 Gratuitous ARP Apr 06 2002 07:41 AM x.s.x.213 Gratuitous ARP Apr 06 2002 07:41 AM x.x.x.218 Ping Apr 06 2002 07:42 AM

Alternatively, all works well after some router reboots.

Cisco IOS Software, C1700 Software (C1700-ENTBASEK9-M), Version

12.4(5a), RELEASE SOFTWARE (fc3) .... System image file is "flash:c1700-entbasek9-mz.124-5a.bin

IOS bug/setting? Polycom bug/setting?

Thanks