Are you on speakerphone when you try to enter the meeting/bridge digits? or on the handset?
I experienced once same issue with what you describe and found that it was caused
by the phone itself distorting the tone that I was entering. My suspicion at the time
was that this artifact was caused by some form of echo cancellation kicking in on the device
or somewhere else on the phone network, or that the looping back the sound of the dialed
digits while on speakerphone was enough to distort the tone to the point that the
conference bridge was mis-recognizing them. The one time I encountered this
was with conf calls using
freeconference.com.
As soon as I picked up the handset and dialed again, all issues disappeared.
L.
