On-demand Call Recording, one sided speech

Make a call to another internal extention and press *1 during the call to record it. The call progresses normally, the other party does not hear the dtmf generated by the *1 (although the calling party does) and all is good.

Hang up and play the call back through ARI and only the originating caller can be heard having a conversation with himself!! The other side of the call is just not there.

Any ideas?