First off before I comment to much, I addressed this in a pre-sales area of the forum as well... But my point is I am a VoIPo reseller and chose VoIPo for many reasons to include with my business. You WILL ALWAYS run into faxing issues via the internet. ALWAYS. If you are trying to use an actual fax machine you have to mess around with the "bog" rate of send and slow it way down in order for it to work. Broadband sends information MUCH faster than copper lines. I copper line tops out at 48.8k if a single loop. Changing your settings on your machine can help you.

My best advice is to get an e-fax number from VoIPo attached to your current account and do straight e-faxing. My business doesnt use voipo efax, but I use a different solution, but i have tested voipo and it works just the same. The sending of e-fax's with PDF's out and in is so much more simplistic and the way things are going to go anyways.

Wish you the best of luck.