I recently had a situation similar to yours that was cleared up by using Advanced Outbound NAT.
----- "Sterling Windmill" <sterling dot windmill at custdata dot com> wrote:
> Since I upgraded my home m0n0wall (running on ALIX) router to 1.3b14,
> I am experiencing an issue with my VOIP provider (Via Talk) that I am
> assuming is a side effect of the newly added nat source port
> My calls get placed or are received, but I cannot hear the remote
> caller once the call is established.
> I have worked around this problem temporarily by assigning a static IP
> to the VOIP device in a 1:1 NAT configuration, but I imagine I am in
> the minority for having an extra IP available for this purpose.
> Is it possible to selectively turn off source port randomization for
> certain IPs? Is my VOIP provider doing something it shouldn't be? Any
> BTW, here is the forum thread I referenced:
> Sterling Windmill
> Systems and Technology
> Phone: 586-752-9671 Ext 161
> Fax: 586-752-6589
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