MSDL ERROR: MSDL O ACTV_ST: RLS EST_REQ

[LargeHadronCollider0]

Hi,

I have a CS1000 geographic redundancy in release 7.5 and on a remote media gateway I have a UDT card with an error referring to the MSDL:

DCH: 48 MSDL O ACTV_ST: RLS EST_REQ
DCH: 48 MSDL The ACTV_ST: W_EST RLS_IND
DCH: 48 MSDL O ACTV_ST: RST RESET_REQ
DCH: 48 MSDL I ACTV_ST: RST RESET_CNF

% DCH: 48 MSDL I ACTV_ST: RST CALL_REF_BLD_ACK
% DCH: 48 MSDL O ACTV_ST: REQ EST_REQ
% DCH: 48 MSDL I ACTV_ST: W_EST EST_CNF
% DCH054 DCH: 48 EST CONFIRM TIME: 10:18:37 19/07/2013
%
% DCH: 48 MSDL I ACTV_ST: EST RLS_IND
% DCH055 DCH: 48 RLS NO RESPONSE TIME: 10:18:41 19/07/2013
%
% DCH: 48 MSDL O ACTV_ST: RLS EST_REQ
% DCH: 48 MSDL I ACTV_ST: W_EST RLS_IND
% DCH055 DCH: 48 RLS NO RESPONSE TIME: 10:18:45 19/07/2013
%
% DCH: 48 MSDL O ACTV_ST: RST RESET_REQ
% DCH: 48 MSDL I ACTV_ST: RST RESET_CNF
% DCH: 48 MSDL O ACTV_ST: RST DSBL_REQ
% DCH: 48 MSDL I ACTV_ST: RST DSBL_CNF
%
% SDL000 PRIE (MSDL 28 0 1 ), VERSION 87 , MAINT MODE.
%
% DCH: 48 MSDL O ACTV_ST: RST ENBL_REQ
% DCH: 48 MSDL I ACTV_ST: RST ENBL_CNF
% DCH: 48 MSDL O ACTV_ST: RST CALL_REF_BLD
% DCH: 48 MSDL I ACTV_ST: RST CALL_REF_BLD_ACK
% SDL000 ITA1 ( MSDL 28 0 ), VERSION 54 , MAINT MODE.
%
% DCH: 48 MSDL O ACTV_ST: REQ EST_REQ
% DCH: 48 MSDL I ACTV_ST: W_EST EST_CNF
% DCH054 DCH: 48 EST CONFIRM TIME: 10:19:05 19/07/2013

After these errors repeated many times, the d-channel is disabled and must be rehabilitated sometimes by hand.
I can not find anything on this topic, you can give me a hand?

thanks