HyperCard 2.0: Sound Changes

I have developed a "Vocal Communicator" stack that takes advantage of MacinTalk (Apple, Jan. 1 1983) and several XCMDs and XFCNs from HyperMacinTalk v1.0 (Copyright 1987, by Dennis C. DeMars). This stack worked perfectly on my Macintosh SE/30 under System 6.0.5 and HyperCard 1.2.5. With it, a mute person can answer questions and build sentences to be spoken aloud by the Macintosh. After I upgraded to HyperCard 2.0, all it would do was beep, or remain tied up and silent for the length of time that should have been spent "talking."

Is there something about HyperCard 2.0 that makes it incompatible with existing XCMDs or XFCNs?
HyperCard 2.0 has changed the way XCMDs and HyperCard interact when using the sound capabilities of the Macintosh. Specific callback procedures have been added that XCMDs (and XFCNs) can use to signal HyperCard when they want control of the Macintosh's sound channels. It is likely that XCMDs using sound will need to be modified to work properly with HyperCard 2.0.
Published Date: Feb 20, 2012