I found a way to play audio in the Hype interface - no need to Preview. QuickTime 7 Pro makes the following easy, but almost any video editor would suffice I imagine, though the exact steps would not be the same.
One possible routine:
• Open your soundtrack in QT7.
• Paste an image - doesn’t matter what - using “Add Selection & Scale”.
• Save.
• Extract the soundtrack out of the file & “Save as…” a .mp4 or .mov - basically avoid audio suffixes.
• Insert into Hype as a video (or drag’n drop).
In addition to playing audio in the Hype environment it also has a visible presence on the Timeline, look under “Properties” - You will see “Video Track” with your sound file’s duration accurately depicted. Though there is no waveform it is a step up from nada.