Chappy this comes up all the time with people who are not familiar with midi. It takes a book to go into it all but the two main things that get people are patch changes and volume changes. Those are embedded in the file itself and will override what you as the user are trying to do if you don't understand it. If the person who created the file uses a flute in a GM synth, and you are using a GM synth for sound no problem but if that person used a non GM synth say a Roland or Yamaha then that flute patch number will trigger something else unless you are using the same synth. The second thing is volume changes. You can be in Real Band, spend 15 minutes setting all the volume sliders to get your desired mix and then watch it all go away when you hit play again. Why? Because there are embedded volume changes in the midi file so every time you hit play those override what you just did. Saving the song doesn't help, you have to go into the event list and modify those volume cc's first then save the song.
Midi can be tricky and it requires study.

Bob

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