#1 Add reference to playing CSegment so it doesn't get GC'd

[Jason Hendrickson]

From Thomas:

I think it may be worth bringing to your attention, I struggled with a bug in my program for about a month where the music would cut off after a little bit of playing. I realize now that it was because I declared the CSegment as an instance variable and GC collected it when it came time. If you ever plan on releasing another version, it may be worth adding in a reference to playing segments, so they're not lost in collection.