You can disable dialtone detection for all outbound calls if you need to, however it is a little dangerous. This essentially means when we go off hook to do a dial, we wont check for dialtone at all, we'll just start dialing. If you have ports doing dial outs also answering incoming calls this sets up the possiblity of collisions where the incoming caller will get a bunch of TTs in their ear instead of the opening greeting. Not cool.
If you need to do this, make sure you dedicate ports for dialouts.
It does require a registry edit and a restart of Unity. As always, do please be very careful when editing the registry. OK... that said, here's where you need to go in the registry:
"HKLM|Software|Active Voice| MIU | 1.0 | Initialization|"
you'll see a key called "Collisions Disabled". By default this is 0 (meaning off). Set it to 1, restart Unity and we will no longer check for dialtone on dialouts. Remember, this is a system wide parameter, not a per port thing so be careful.
good luck.
Jeff Lindborg
Unity Product Architect
Active Voice Corp
jlindborg@activevoice.com