I have a vocal line I'm editing in Melodyne. There are two E's that I want to be F's.  I grab one E blob and move it to F.  Then I grab the second E blob and do likewise.  The first blob moves back to E. If I go back and change the first one the second reverts.  I reported this to Melodyne.  They suggested I open a new project and see if the problem persisted.  I opened a new project, sang a few notes, moved them around, no problem.  Then I started another project, recorded some tracks, did a vocal, started to edit it, and the same problem arose.
Melodyne also suggested I re-install the program.  I did.  No difference.
I'm new to Melodyne--am I missing something?  BTW, I tried the same thing with V-Vocal and it worked fine.

I have been burned by plug-ins a time or two, so the only suggestion I have is to copy that track, and try the same thing in Melodyne in stand-alone mode and see if it is repeatable. Have you tried that just to rule out a possible ARA issue?

Ok, so I dragged the file from Sonar to Melodyne standalone, moved the notes around, and it seemed to work.   Only problem was the program crashed when I tried to close it.  ARA problem, then?

The "crash" when closing is concerning, but I would recommend reporting it to Cakewalk as well, just so that it gets visibility. I am totally new to ARA, and in theory it sounds wonderful, but requires a lot of handshaking between programs.

Just so you have full information for your report, 1-Was Snap on or off in the pitch grid, and 2-Did you try using the pitch tool to click on the end of a note and disconnect the pitch transition?  (Pitch Transition is that yellow line that connects notes.)  I am really curious if #2 would make a difference?  You shouldn't have this problem no matter what but it would be interesting to see what affects it.

[Konrad said: 1-Was Snap on or off in the pitch grid, and 2-Did you try using the pitch tool to click on the end of a note and disconnect the pitch transition?]
 
Here it is nearly 2 years later and I just started using Melodyne Editor as a plug-in in Sonar X3 64 bit in Windows 7 and have the same problem.
1-Snap was off.
2-It occurs 2 bars away from where I am changing the pitch, so I would not think the pitch transition would be relevant.  (It also occurred when I used the program yesterday in the same bar.)
 
Specifically, when I move a blob at A# down to A, it moves a C two bars away down to B.  When I move the B back to C, the earlier note goes back to A#.  When that happens, the Scale Editor also changes from C major to D major.  I do not want this to happen!!!
 
I am wondering if this has something to do with the way Melodyne handles scales, which I can change, or if this is just an ever-continuing BUG in the way it works within Sonar.  Also wonder if others are still having the same problem in using Melodyne Essentials rather than Editor, or if using Sonar 32 bit might make a difference.
 
I am wasting a LOT of time, having spent hours searching the Melodyne manual before hitting the forum.  Would really appreciate some answers if anyone has any.  Thanks.

It sounds like you might have those 2 notes or blobs highlighted at the same time.
Click on an open space to make sure that you are not selecting anything.
Use the manual mode, by holding either Alt or Shift, may be Alt, then move the note around.
Make sure that you are pitch correction mode.
dan