[Asterisk-Users] grandstream asterisk configuration

[Owen Kelso]

>  I have the following configuration:
>
>  Grandstream --> NAT (Netgear RP614)-->Internet-->Asterisk(public IP)
>
>  i can register fine and call ringing is working as good. The problem is
> i cant hear audio both ways and i get this error:
>
>  WARNING[22544]: File rtp.c, Line 375 (ast_rtp_read): RTP Read error:
>  Resource temporarily unavailable

Chandra,
I have this _exact_ same problem and it's the Netgear router corrupting
the UDP checksums in the RTP packets.  Specifically, the checksums come
out of the phone unset and the router is setting them to incorrect values.
 Netgear has not yet responded to my support requets.  Ethereal will
confirm if you're getting the same thing.

Swap out the Netgear with a Linksys or other router and I bet it works.