This is what lostpedia says about it:
The incomplete numerical sequence dictated by Bonnie is 5-4-5-8-7-7-5-5-4-3-7-7-6-1-1-3. However, the audio of this scene does not match the pattern of the changes of notes as given by Bonnie, nor does it match the sequence of note-changes shown on the video of the scene. For example in the audio, the second and third notes are different, yet the video shows Charlie pressing the same note (5). The melodic code heard in the episode is in C-Major, and the 19 specific notes of the code as played by Charlie are: A G A C C D D F G G G F A A G F C D C.
But anyhow, about the TOPIC.
Interesting find about Stratton/Strutter, Amy. Lots of Rock stars change their names, or the spelling of their real names. Not saying this was the same guy because Dexter Stratton seemed to be Charlie's mom's dad's dad or something like that? So too old. But it would be neat if there was a family tie in there somewhere!
I would like to see more musical code in the dharma hatches. More specifically related to Geronimo Jackson. If the musician programmed one thing maybe he programmed another? Anyhow, my impression was that the musician in question set up the security code which was after the purge? So was it instructions from Ben directly? Is the musician still alive then, and on the island? I'd hope so....!