FreePBX (asterisk) Sipstation Cisco ASA 5520 Trunks Won't Register

FreePBX (asterisk) server ip 10.7.4.23

The is is what Sipstation is telling me they are seeing on their end:
2013-12-29 16:31:42.702739 [WARNING] SIP auth challenge (REGISTER) for [[email protected]] from ip 10.7.4.23

So my cisco ASA5505-K8 is showing the sipstation servers my internal IP address and not the external IP.

I can’t setup a static nat for 5060 as I get an error: NAT unable to reserve ports. I think this is because of the inspection map.

I have tried unchecking sip and H.323 in the service policy rules.

You still must have the SIP ALG on in the ASA.

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