Grand 3 new user. Nasty digital noise in Logic.

Grand 3, brand new to me, just installed two days ago, creates a nasty, rude digital noise-burst
making it pretty much unusable.

I can record Grand 3 piano tracks in Logic Pro 9, in Mavericks 10.9.5, but when I go to record a different software instrument track after that, in the same song, pressing record summons up a horrible, loud digital noise. So it is somewhat usuable, I have created some songs OK, but - more than half the time when I try to add another (different instrument) track after recording a Grand 3 track, I get horrible digital noise upon pressing record or play.

Before using Grand 3 at all, I DID install the four discs of 3.0, then the 3.1 Grand update, and then I DID install the CoreAudio patch after reading how important it is etc.

Later I wondered, “that CoreAudio patch was probably designed to fix a problem in an early version of Mavericks. Maybe I should not have installed the CoreAudio patch at all?” :question: But I do not know how to
uninstall the CoreAudio patch to test that theory. I do not know how to retrieve an older version of the CoreAudio thing (is it a driver?) from a backup either. Or maybe the patch didn’t really install? :question: Or maybe Grand 3 doesn’t really work with Logic Pro 9 in Mavericks 10.9.5? :question: These are questions I don’t know the answers to.

Can anyone help me fix this? Or tell me who to ask? Grand 3 is pretty much unusable and I will have to uninstall it unless there is a fix for this noise problem.

thank you,
Wade C.
Dallas, TX

Bye and Best wishes everyone. Moving on to Ravenscroft 275 and Pianoteq 5 today. Unhookin’ the dongle.