Change FPBX useragent(server)

1

Hi. There is a problem of changing “useragent” for FreePBX.
Now i have this construction when incoming call:
CSeq: 102 OPTIONS
Server: FPBX-13.0.192.16(13.17.0)
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE

How to change “Server: FPBX-13.0.192.16(13.17.0)” to “Server: FPBX-13.0.192.16” or else?
My VOIP-provider believes that both directional silence after dialing is caused by hooks on
Server: FPBX-13.0.192.16(13.17.0) ?

Thanks in advance.