One problem I've noticed with my new Mac Pro is that my collection of MIDI files doesn't play properly. Some instruments cannot be heard, and the playback skips and stutters. This happens not only with all the MIDI files I've saved on my computer, but also MIDI files found on the Internet that I play in any browser using the QuickTime plug in. This problem occurs when using the standard QuickTime MIDI sounds or with any of the fancy sound fonts I've installed.

I am using QuickTime Player 7.2. Is there any solution or cure?

This may not seem such a serious problem to those used to MP3 files, but I actually prefer MIDI, and it has the advantage that if I open a MIDI file in GarageBand or a notation program, I can see the sheet music.

At every site with MIDI files, the playback skips and ticks.
One is http://www.ragtimemusic.com/midi.html#top%20of%20page
another is
http://www.johnroachemusic.com/midiragger/bozo_sb.mid
another:
http://www.classicalarchives.com/
and another
http://www.kunstderfuge.com/midi.htm

Click on a file, listen to it play, hear it snap, crackle and pop. This never happened with QuickTime 6. I sure hope it doesn't happen to you, but it sure is annoying to me.

I tried a file from each of the sites you listed (except the 3rd one where you need to sign in). No snap, crackle, pop or skips on my Mac Pro.

What are your system specs(CPU, RAM, OS level)? What else is running? Have you looked at the Activity Monitor while this is happening to see if something unusual is going on? What are you using for a speaker system?

I'm with Jack on this one. I'm hearing nothing out of the ordinary on my Intel iMac with all the latest software updates.

Do the problems occur if you download the file and play it locally instead of playing it from the 'net? If so, you may have a networking issue.