Hypothetical question

We have replaced several OEM Asterisk based systems that had proprietary phones. We have several installations. The phones basically work, but there is a very high incidence of calls dropping. I paid for support to get into one of these systems and no cause was found. In looking at some packet captures I noticed that the useragent is asterisk on the replaced system and Freepbx-2.11 (or something like that). Here is the hypothetical part, would it be possible to us the useragent info to manipulate the phones to not work correctly? Grasping at straws here actually.

What is the phone model?

It is an IPitimy hd320 – Actually a Escene ES320

The Escene phone was OEM’d to IPitomy and they reworked the firmware. I tried to upload a version from Escene with no success.

Must be a tough nut to crack. No ideas?