no ip proxy-arp will impact any voice traficc incomming and outgoing calls.
when i disabled the proxy-arp in the vlan500svi,the outging and incomming calls disrupted.
internal calls are working fine.
we have seen that the VGW is connected to another IP subnet in Vlan 221.
In vlan 500, where you have disabled the ip proxy-arp there can be IP phones and/or the Call Manager/ IP PBX
For Cisco CallManager:
Signalling is between Call Manager and IP phones (SCCP or SIP) and between Call Manager and voice gateway (either using H.323 or MGCP).
RTP VoIP streams for the VoIP call leg is between the Voice Gateway and the involved IP phone.
No direct signalling traffic flows between the IP phone and the VGW.
Or signaling had been broken or the RTP stream had been broken, when you disabled the IP proxy ARP in Vlan 500 SVI.
Hope to help