Recordings are perfect, end user reports poor quality

Hey everyone, I’ve posted this on the PIAF forum as well and before I pay for some support from Schmooze I thought I’d ask here.

Situation is so:

I recently have been having an issue with a client. Here’s the config:

10 57i phones,
PIAF INFO:
PIAF VERSION = 2.0.6.4 under VIRTUALBOX
FreePBX Version = 2.10.1.9
Running Asterisk Version = 1.8.22.0
Asterisk Source Version = 1.8.22.0
Phone Firmware: 2.6.0.2010

Phones on separate VLAN from PCs with separate route to the internet.
15 Windows PCs on a domain

They have been have been having issues with call quality, so I started recording all the calls. The calls the users are reporting don’t match up with the recordings. That is to say, they are noticing call quality issues (crackling, popping and clipping) but when they listen to a recording of the same call, it is perfect.

How do I find out where the problem lies?

Oops I double posted…