[Freeswitch-users] Recommend an IP Phone for use behind NAT

I am looking into changing my VOIP server to FreeSwitch. My current system uses Polycom SoundPoint IP 335 phones. The server has a public IP, but several of the phones are behind a variety of DSL routers that do NAT. These remote users have reported intermittent problems with one way audio. What IP desk phone would you recommend for a remote user behind a NAT router with a dynamic IP? I'm looking for something of comparable audio and build quality to the Polycoms I currently have. Thanks, Alan