CDR - hang repeatedly appears

I setup and deployed my FreePBX/Asterisk server a few weeks ago and it works ok. We can make and receive calls fine. The issue I am experiencing is related to the CDR’s (Call Detail Reports). I have included a section of my CDRs below.

System Specifications:
[] FreePBX 2.4.0
] Asterisk
[] Digium TDM808B (0 FXS Ports/8 FXO Ports) - Only 5 are in use
] Used PBX in a Flash ISO
[] Installed A2 Billing module, not used, CDR was messed up before
] A single IVR is used and receives all calls. No DIDs. Only one incoming route for all calls and all DIDs.
[*] Hunting and rollover is enabled on all POTS lines by service provider (Cox Communications)

Date Channel Source Clid Dst Disposition Duration
2008-04-30 14:00:38 Zap/5-1 hang ANSWERED 01:17
2008-04-30 14:00:17 Zap/4-1 hang ANSWERED 01:17
2008-04-30 14:00:04 Zap/3-1 hang ANSWERED 01:17
2008-04-30 13:59:53 Zap/2-1 hang ANSWERED 01:17
2008-04-30 13:59:46 Zap/1-1 hang ANSWERED 01:17
2008-04-30 13:25:10 Zap/1-1 3306665514 "OHIO SOFT TECH " <3306665514> 1002 ANSWERED 03:29
2008-04-30 13:24:42 SIP/1003-b… 1003 “Scott Cupit” <1003> 1002 ANSWERED 00:19
2008-04-30 12:45:08 Zap/1-1 8772411442 "800 Service " <8772411442> s ANSWERED 00:15
2008-04-30 12:35:31 Zap/5-1 hang ANSWERED 01:17
2008-04-30 12:35:11 Zap/4-1 hang ANSWERED 01:17
2008-04-30 12:34:57 Zap/3-1 hang ANSWERED 01:18
2008-04-30 12:34:47 Zap/2-1 hang ANSWERED 01:17
2008-04-30 12:34:39 Zap/1-1 hang ANSWERED 01:17

Why are my zap channels cycling through one after another? I have tried to contact the phone company and they say there is no problem on their end. I can actually see this happen on the flash panel in real time. The caller id says either unknown or loop, then at 1:16 the caller id goes to hang and the system hangs up. I assume that these calls go to the IVR, where the IVR times out and hangs up as it is supposed to, but it does not appear that anyone is calling during those times, this seems to be automated.

I am trying to clean these reports up so that we can use them for internal reporting and record tracking. In addition, it seems something is wrong with my system because it ties up all trunks blocking everyone from dialing out and receiving calls.

Any help anyone can offer would greatly appreciated. I have tried to locate other forums where users have experienced similar issues but I have been unsuccessful. I am more than happy to post config files and additional logs.

Scott Cupit