Ujo Ales

I'm a newbie and have one basic question. I try to make IVM work as a VoIP only solution. Do I really need to use voicemodem even if it won't be connected to phone line? I tried it on two computers and encountered two different problems: First of all I tried it in my notebook IBM R40 and it worked well when I called from other computer using SJphone or using call simulator. But when I tried it using SkypeOut or landline it didn't react to any DMTF commands. Is there any possibility to "teach" the notebook correct DMTF responses? After that I installed IVM at another computer without modem and call simulator works still well. But when I call from other phone (SIP-SJphone, landline, Skype) I don't hear any sound (although IVM says that it plays messages correctly). After that I have tried 3 different PCI modems (every one states it is voice capable) but still the same - hear nothing. Of course I uninstalled/installed different drivers for these modems but nothing helped. It is curious that I have to buy the analog modem to use VoIP solution, isn't it?