Hi,
I have it configured on my system without a join tone, and in that regards it is silent. On my system at least, I hear a slight connect as the call is conferenced. Those join tones sound like fire alarms... The other party will see the barge on their screen though:

To remove the join tones: (please double check your config to make sure profile # and join/leave tone names are what are used in your config)
You may first need to shutdown the dspfarm before you make the change if it is active. This will disconnect any active conferences. Then bring it back up with no shut when you are done. I have included them below, use as necessary. You will need to confirm the the shutdown command with a yes.
config t
dspfarm profile 1 conference
shut
no conference-join custom-cptone CCAjointone
no conference-leave custom-cptone CCAleavetonene
no shut
Remeber to test, then save your changes.
Hope that helps.
Best,
David
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