Bug report for T24M with

not sure where in can post a bug report… nevertheless: i try it here.
I recently installed MX-V4.4.2.73 over my MX-V. on my T24M.
I use a special SIP ring tone - and an asterisk SIP server for call management (not the embedded one)

With the upgrade to the 73 i experience a strange behave: the ring tone is a very long one (the jeopardy melody… maybe 40 seconds). When i pickup the call the people in front of the T24M cant hear me.
The ringtone still plays - but i can hear the people at the same time (with the jeopardy ringtone in parallel).
Downgrading to version brings the doorbell-behave back into normal situation (as seen with all earlier versions… running since 8 years all upgrades).

Is there anything i can help providing a bug report, logfiles, …?

(german or english language is apropirate)