VOIPo/Apple Airport Issues

Hopefully someone will be able to help me on here with regards to an issue I'm having with some select outgoing calls. I've got the Cable Modem connected to an Apple Airport Extreme, and plugged into that is my VOIPo unit. Everything seems to work ok with the exception of placing calls to a few numbers, when I just get 'dead air' and then a fast busy signal. The receiving party state their phone rings and when they pick up, sometimes they hear me, sometimes they get 'dead air'. I can never hear them, all I get is a fast busy signal after about 30seconds.
I've called Tech Support several times with no luck, they've even remotely accessed my computer to try and alter the Airport settings, with no joy. I've read several forums where they talk about altering the NAT settings or some sort of Port conflict. Anybody have any clue how I can go about fixing this issue? I'm not too familiar with altering these settings, so any help would be appreciated.
I know the problem now lies with the Airport, as I have isolated that and simply plugged the VOIPo unit directly into the back of the Cable modem without any calling problems.
The problem is getting old real quick! What started out with a few select numbers, seems to be growing by the day, with the same issue happening on too many calls now!

Thanks for any help any of you can provide!

Hey,

Have you tried using the Airport's DMZ option? Apple calls it "default host" in the airport.

This post from apple's forums has some useful info about setting this up:

http://discussions.info.apple.com/me...ageID=11508004

Let us know how it works out!

Thanks Lucas, Ok did that and tried it, it works for one number I was unable contact, yet still having issues with others. Call and get about 30 seconds of dead air before a fast busy signal. Again other party answers after it rings on their end, yet no one is there? I just get nothing except busy signal!!! No idea what's going on!

Hello,

I'd recommend contacting support@voipo.com for further troubleshooting if you're still having problems.

It appears that STUN has been enabled for the device. If you're still having problems, we can further tweak some setting to hopefully get it working properly.

Submitting an email that opens a trouble ticket is the best way for us to work on this issue so that we can exchange information that would normally be private (not suitable for a forum post).