Alex -- are you using a VoIP software phone on your computer, or do you
have an external VoIP box?

Here are my rules which I'm using to good success with my Vonage VoIP box,
which is "vox," below.  Let me know if you need to see an example of traffic
shaping to increase the priority of VoIP traffic, I think I've got that sussed,
as well.

     <nat>
        <rule>
            <protocol>udp</protocol>
            <external-port>69</external-port>
            <target>vox</target>
            <local-port>69</local-port>
            <descr>VoIP</descr>
        </rule>
        <rule>
            <protocol>udp</protocol>
            <external-port>123</external-port>
            <target>vox</target>
            <local-port>123</local-port>
            <descr>VoIP</descr>
        </rule>
        <rule>
            <protocol>udp</protocol>
            <external-port>4500</external-port>
            <target>twowords</target>
            <local-port>4500</local-port>
            <descr>VPN traffic</descr>
        </rule>
        <rule>
            <protocol>udp</protocol>
            <external-port>5060-5063</external-port>
            <target>vox</target>
            <local-port>5060</local-port>
            <descr>VoIP</descr>
        </rule>
        <rule>
            <protocol>udp</protocol>
            <external-port>10000-20000</external-port>
            <target>vox</target>
            <local-port>10000</local-port>
            <descr>VoIP</descr>
        </rule>
     </nat>

[...]

     <filter>
        <rule>
            <interface>wan</interface>
            <protocol>udp</protocol>
            <source>
                <any/>
            </source>
            <destination>
                <address>vox</address>
                <port>5060-5063</port>
            </destination>
            <descr>NAT VoIP</descr>
        </rule>
        <rule>
            <interface>wan</interface>
            <protocol>udp</protocol>
            <source>
                <any/>
            </source>
            <destination>
                <address>vox</address>
                <port>123</port>
            </destination>
            <descr>NAT VoIP</descr>
        </rule>
        <rule>
            <interface>wan</interface>
            <protocol>udp</protocol>
            <source>
                <any/>
            </source>
            <destination>
                <address>vox</address>
                <port>69</port>
            </destination>
            <descr>NAT VoIP</descr>
        </rule>
        <rule>
            <interface>wan</interface>
            <protocol>udp</protocol>
            <source>
                <any/>
            </source>
            <destination>
                <address>vox</address>
                <port>10000-20000</port>
            </destination>
            <descr>NAT VoIP</descr>
        </rule>
     </filter>


Adam

-- 
Lose your mind and come to your senses.  -Fritz Perls          <adam at baz dot org>