Customer Hanging up phone after call has been send to agent

[optimusvoice2012]

We are experiencing a lot of calls being send to agents late. For example, the agent will hear the customer hanging up the phone already. And it happens a lot this days. We are not experiencing this before or maybe minimal. Confusing is, this only happens a lot or maybe this only happens on UK calls. As we have 2 shifts. US calls are not experiencing this problems. We already address some problems with the carriers like cut lines in the middle of the call, but we don't know if they fixed everything already. We also experiencing dead air, which i only think of the provider and maybe the g729 codec.

Vicidial version: SVN 2.6 (still using vicidialnow 1.3 as we are using this for years now and doesn't have bad experience like we have now), but we are planning to use Vicibox anytime soon.
Asterisk Version: 1.2.30, we are planning to upgrade to 1.4.39 anytime soon. But we really have good experience on the old version.
We are using AMD on all campaigns.
This are all auto dials.

We are looking AMD as the main reason of this problems. Sending answered calls to agent late enough that the customer will hang up, and the agent will hear ir.
I'm also looking on network congestion. Could be a switch congestion that causes late transfer. Or overload of a server.

Hope someone has an answer to this problem.
Thanks!

[optimusvoice2012]

Main Issue on this could be the VoIP Provider: (large amount of Dead Air, Cut Lines, Delay)

We believe that there is some changes on UK route of this VoIP Provider that resulted to this. Yes we are experiencing and should be experiencing this as we are on VoIP/SIP, AMD, but it never happens that a large amount of this problems is being experience by agents. And the thing is, it only happens in UK calls not on US calls.

Plus, when are changing to backup VoIP Provider, the managers said that they are not experiencing it.

We will also convince the owner to buy sangoma cpd, problem is as always they would like to cope up on what we have.

[potpot]

we experience same problem

in our side we experience abandon calls like the calls being send to the agents. early hung up like for example i recieve the calls but no one is in the other line it is already hung up .

mu question is why we recieve calls drop calls . if it is drop calls;
or why we receive alot of abandon calls

thanks in advance.