Unfortunately CCA does not give you the option to enable/disable the join/leave tones. They are configured by default. If you use the software resources (IOS) for 3-party conferences (uncheck Enable Multi-Party Conferencing and select Max 3-way calling sessions) it would not play join/leave tones for ad-hoc conferencings. But you only get ad-hoc conferencing - no meet-me or more than 3-party ad-hoc/meet-me. You also would be disabling cBarge.
If you remove it OOB, I don't see it causing a problem with CCA since all CCA does is remove or add these commands when you enable/disable hw conferencing.
dspfarm profile 1 conference
no conference-join custom-cptone CCAjointone
no conference-leave custom-cptone CCAleavetone
However, I don't recommend getting into the habit of doing OOB configurations since it's a very gray area and the behavior of how CCA implements a feature may change b/w versions.
Technical Marketing Engineer
Small Businss Technolog Group