About the only thing you can do is to have some kind of network analysis package capturing packets all the time at a point or points on the network that all the calls flow through, then when a call gets flagged pull the logs for that timeframe and see what the network analysis says.
Wireshark is installed on the Edge and you can get the SIP packets by turning on the Protocol Capture logging, but that doesn't help much for the audio problems.
Turning on Media Capture would give some useful info, but only Customer Care can decrypt the files, so it doesn't help you get the info on your own. Wireshark running on a machine connected to a mirror port on a switch with the edges which can access all the RTP traffic going through the edges is your best bet.
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George Ganahl CCXP, GCA
Principal Program Manager
Genesys
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