Previous marker command glitch

[emilenitrate]

I use key commands to move from marker to marker but I've found that there's one marker in my project that cannot be backed over with my previous marker command. I can use my command to go forward past it but then not back over it and I can't understand why. I've inserted the icon command in the tool bar and I still get the same behavior. I haven't found anything unusual in the marker list. Anybody have any idea why this might be happening? Thanks. - Emile