Post Inbound jitter on Quadro M12Li!!

[harrymickenzy]

I am hoping someone can shed the light on this very strange issue.
This system has been installed since last year October with no issues. 3 weeks ago we started with inbound jitter which is really bad... OUTBOUND calls being perfect.
We VoIP calls out over a NeoInternet (1:1 contention ratio).
Neotel say that there is nothing wrong with their fibre.
Wanatel (Voip provider) say there is Nothing wrong on their side.xvideos xnxx xxx

the strange things are:
1. The 4 x T28P phones on the system are 100 fine with ALL inbound calls. The T21P asnd RTX ISERVE DECT PHONES are having a issue. Set up with same Codecs ect.
2. If i dial from Wanatel to Wanatel the inbound call is 100%, but from other external number the T21P and ISERVE calls are inaudible.(bad jitter)

I have attached logs for an inbound call for ext 971
Any Ideas?