DanWHR,
It could be several things, but you need to start narrowing them down one by one until you find the problem. This normally could be done in a couple of hours of testing at most.
Make sure they are using the Handset and they are talking directly in to it and not holding it on their shoulder with the mic under their chin.
If they still have issues then replace the handset and see if the mic in the handset is bad. Normally if no one inside the office is having a problem hearing them the handset is not the issue.
Next have them call you on your cell phone and see how the call quality is versus an internal call. If you are not able to recreate the issue then maybe they are not following their normal process if you are standing in front of them, but most likely the issue isn't with the phone at that point.
If it seems as though the call quality is poor versus an internal call with that phone then you can transfer the call to another extension and see if the call quality gets better. If it does then transfer it back and see if it drops back down again. If it does then just hit the speaker button and see if the problem persists or gets better. If there is nothing you can do with the phone that seems to make it better then look at the Echo settings for the phone if it seems to be an Echo problem. If it doesn't then just replace the phone.
Thanks,
TE
