Excuse me for resurrecting an old thread, but I'm having this same issue.
The Tascam DP-32SD Owner's Manual states on page 51:
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Deleting a location mark
You can delete marks when the recorder is stopped.
1. Press the F FWD (,) or REW (m) button to move to the mark that you want to delete.
2. Press the MARK SET button to delete the location mark.
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Sometimes this works, but more often than not it refuses to delete location marks. Needless to say, it's extremely annoying to have marks where they are no longer required.
I contacted Tascam Support via email, who advised me to set the In/Out marks to zero then try deleting the other marks I created. I did so and then starting from zero, used the FF key and pressed "Mark Set" on each one. The location marks were being deleted, yay!
But, UH OH.
When I run into the last three marks near the end of the song, they refuse to delete. The really strange part is, I can go to any of those three marks using FF or REW then press “Mark Set” and the mark number text at the top of the screen (MARK XX) disappears along with the red mark on the timeline display, just as if the mark was indeed deleted. But, when FF or REW are pressed, the transport still stops at those times as if the marks were still there.
I am running the latest firmware (V1.01), although this issue existed with the original firmware as well. Tascam support is now suggesting I send the unit in for service, but it's out of warranty so I don't want to go that route. This sure seems like some sort of firmware issue to me anyway, but who knows. Everything else on the recorder functions perfectly.
As a side note, does anyone know if there's a way to perform a “factory reset” on this recorder? I know you can reset preferences in that menu, but I’m talking about a total, fresh out of the box reset. I suspect not, as I can’t find anything in the manual about it, although that sort of thing is often undocumented. Just a thought, maybe that would fix the problem.
Thanks in advance for any advice you can offer!