asterisk users - Mar 2005 - SNOM 190 Loud Ring While on Speaker

When on a speaker call on the SNOM 190, a second calls comes in and the
ring is VERY loud and heard by the remote party.

Is there a way to set the dialplan in * for a "silent" ring for the
second (or third) call.

Is there a way on the snom to change the ring to a silent ring when on
speaker?

Has anyone else had this experience?

TIA