1) Welcome to the Party!
2) when you post, please post your entire configuration including (but not limited to) your installation method and vicidial version with build.
this IS a requirement for posting along with reading the stickies (at the top of each forum) and the manager's manual (available on EFLO.net, both free and paid versions)
You should also post: Asterisk version, telephony hardware (model number is helpful here), cluster information if you have one, and whether any other software is installed in the box. If your installation method is "from scratch" you must post your operating system and should also post the .iso version from which you installed your original operating system. If your installation is "Hosted" list the site name of the host.
If this is a "Cloud" or "Virtual" server, please note the technology involved along with the version of that techology (ie: VMware Server Version 2.0.2). If it is not, merely stating the Motherboard model # and CPU would be helpful.
Similar to This:
Vicibox X.X from .iso | Vicidial X.X.X-XXX Build XXXXXX-XXXX | Asterisk X.X.X | Single Server | No Digium/Sangoma Hardware | No Extra Software After Installation | Intel DG35EC | Core2Quad Q6600
3) As your OS is Ubuntu 64 bit, I will assume a "scratch install" ... but a link to your installation method would be very helpful. It sounds like an install issue. Which brings up the point: Why not use Vicibox or GoAutoDial for your installation? (This would likely resolve your issue and then you could spend your time making money instead of explaining to your agents and clients why this system seems to NonProfessional ...). If your colo will not allow custom OS's ... the extra money for a different colo would seem in order.
4) That being said, please try three scenarios:
First: Call from Phone to carrier NOT through Vicidial server at all
Second: Call from Phone to carrier via Vicidial server (but no web interface, so the call is just through Asterisk)
Third: Call as logged in agent to on regular campaign.
Then make adjustments and see if any respond differently:
Try each of the above with the "Phone" being IAX and again with SIP
Try each of the above with ulaw, gsm and g729
Try again with a Carrier that is SIP/IAX and codec ulaw,gsm,g729
The concept is to see if any of these have any sort of effect. Are any of the call improved at all.
5) Is your system Virtual or Physical (Vicidial does not work Virtual)?