Undo command malfunctioning in strange way...

Question

I've read a lot of posts about problems with the Undo command.  The problem I'm experiencing seems different.  In the middle of editing, I'll go to Undo something and it usually works.  But sometimes it will only let me undo the last couple or few edits.  Then, if I look at the Edit menu, the Undo option will still be there, and not grayed out, but it does nothing if I click it.  And it just says "Undo."  In other words, it doesn't say "Undo Effect" or "Undo Trim."  When the undo actually is working and does something, it does say "Undo Trim" or whatever.  But, when it stops working, it just says "Undo."
What could this be?
I'm running FCP 10.0.9, and I have 32 GB of RAM.  Everything is updated on my iMac, and it's a pretty powerful one (i7 core).

Answer 1

Personally, I have grown used to rebuilding my autoload at every revision in the tenth placeholder (i.e. 7.0, 7.1, 7.2). Updating environments, things like that. If you need to really curb a corrupted file sometimes you have to go to extremes such as copy/pasting portions of the arrange into a fresh song. I've had to do this AND remove, manually restore plugins and mix settings on a few tracks. It has caused enough problems that I just run several sub sessions and the actual session that provides the mix and final bounce is little more than several contiguous tracks without submixes. If I have to change something I just go to the session. Today i have been working on drums, I have a session for drum editing which contains the 3 best takes. I do my chopping/quantizing and on and on....the session becomes a few MB. At the end I export the tracks and import them in to the master song session. So the master session hardly runs any plugins and requires little more than alot of disk streaming. It is also void of any events and objects which don't belong there, using song backups is my way of storing outtakes. So far this has been working much better (much less song corruption and rebuilding). But of course can be a time killer and take up alot of disk space. 7.2 manages things better IMO, but I started this process a while ago and probably won't get out of it for a while.
Rohan suggested that opening songs in OS 9 has cleared many problems for him, though it's best to hear the method from him.
There are many threads on this subject but they are usually in replies and not topics, so hunting them down with the search function would help. I don't know if Apple would like a massive topic dedicated to it in their forum...? I really don't know. It's good for users but it doe look kinda bad.