Careful with the SetMasterClock setting aka patch 3.
I could have sworn that I saw that being disallowed in the method documentation but I couldn't find it. I probably mis-inheritted from the IDirectMusic8::SetMasterClock() documentation: "If another running application is also using DirectMusic, it is not possible to change the master clock until that application is shut down."
But that requires a test one way or the other so I'm not blocking that patch.