DTMF Duplicate 2 E1

Hello folks!
I ´ve 2 PRI E1 connected to asterisk with PSTN and a siemens PBX connected to each end.

When I call from siemens PBX through asterisk to the PSTN and got the call established I try to dial an extension.

Unfortunately I hear the DMTF tones duplicate and then my call is transferred to whatever extension but the one I dialed.

Any help would be appreciated!!
Regards!
Agus

Tone dialling works by sending the tones down the line. Do you have echo problems that need to be resolved?