[Solved] Melodyne Issues?

Are you on Sonar X3E?
Melodyne is fine for me without buffer changes, I just make sure I edit no more than a minute of clips at a time (I find it easier to manage that way as well i.e. verse/chorus/verse etc).

Cheers..

While Melodyne/Sonar allows you to run many instances and I personally prefer to leave them open, I do believe it's more stable if you bounce them and only have one open while you're working on it.

I'm the wrong person to ask, because I didn't have problems with Essential except for a few times when V-Vocal was in a pre-existing project. But I don't know if the problems were due to Melodyne, V-Vocal, or an interaction. Editor has been equally smooth for me, I can count on it.  
 
My understanding is that the underlying architecture of the Melodyne products is similar, so I don't think it's a case where Celemony says "hey, let's let the Essential people crash and save the good stuff for Editor." They want you to have a positive experience so you'll upgrade. 
 
That said, how much memory do you have in your system? I've heard rumors of memory not being released properly although I wouldn't know how to test for that. Perhaps this might be why shorter sections work better?
 
But another consideration is I usually try to use software in a way that fits the product. To me, Melodyne is for touching up vocals, so I'll open a phrase, fix, bounce, and move on. I don't ask it to keep several multi-minute vocals open while I do other things. If I really, really think I'll need to re-visit a vocal, I'll just work on a copy and hide the original until/unless needed. Overall, I've found Melodyne Editor to be an exceptionally useful piece of software on many more levels than I expected (e.g., as a quick way to level vocals, or transpose acoustic guitar strumming).

Worked with Melodyne again. Opened it up to fix a mistake my student made in an otherwise good take, no problem bounced that, all good. Deleted old track once done and satisfied it was a keeper. Went to use it on a 2 beat phrase on the vocal track, After auditioning it a couple of times as I was tweaking it, the old sputtery "I'm on the brink of crashing" behavior began.(Oh , I did upgrade to Editor). Recall that I killed the old track that had melodyne as a region FX, so it's not a case of having multiple instances of it open. I was able to make the edits and bounce. Delete the track with region FX on it, and all was good, but Jheez! I had the buffer all the way up to 1024 samples(melodyne displays a warning screen telling me to do that.)What am I doing wrong?! I have an i7 machine, 2 hard disks, 16gigs of RAM, no indication that this is unstable, then I feel like I'm running down one of those rope bridges from cartoons that is falling apart just one step behind you. This can't be normal or acceptable behavior. Any tips,or suggestions? I tried using small regions for region FX, but if it can't handle a one or two measure phrase, what good is it?

I'm using Native Instruments Komplete 6 audio. I usually can run it as low as 64 buffers, but melodyne tells me to run at 1024. I have zero stability issues unless melodyne is involved in which case it starts off smooth, then grows more and more unstable. FWIW, I am familiar with the Delta 66 ( I used the OMNI) the cards seem pretty similar to me, although I'm running the Komplete via USB(3 which uses the intel drivers , it has never crapped out on me). Right now I am running 1 instance of Roland TTS with multiple outputs (4 midi instruments) about 6 takes of my student's on a comp track, two of myself,1 stereo drums track. 1 track of vocals routed through TCHelicon Voice Live GTX. (that's not engaged, but I bring it up because I used it to generate two background voices on the same track as the lead) 1 track of Amber Piano and half a dozen plugs on the buses and some minor pro channel stuff at the track levels on most , but not all tracks. The behaior manifests itself as follows: Select region FX say two bars long max and as small as a couple of beats. Opens up Melodyne editor. audition it a few times, make subtle corrections, listen again. After listening to it 5 or six times , I start to get some stuttering and distortion, no necessarily a dropout, but I feel like I am knocking on the door. At this point I feel compelled to bounce any corrections to a separate track before something bad happens. I hate the idea of having a thoroughly robust system, that can take just about anything you throw at it  buckling under 1 instance of melodyne. I have to believe they know this plug is a CPU pig, otherwise they wouldn't tell you to up your buffers to 1024. So to cap this, I can use it and make effective changes, but I'm definitely playing it's game and when I start to hear it sputtering, yikes!

I agree with Craig but here are my thoughts as well:
 
• Pitch drift's effect depends on how the note was recorded.  If the pitch obviously varies from the root note—like it drops off, or goes sharp, or starts too low and slopes up—the tool will get it more centered on the note.  You may have to drag, then release the mouse button, and drag again because it makes a very small correction each time.  You may also have to use it and then the pitch modulation tool to fix a note.  Example: you fix a large drop off with the drift tool, but then the whole pitch line is above the desired pitch, so you will have to use a touch of modulation tool and maybe the pitch tool to get things sounding right. Sometimes a pitch slope is good but you have to use your ears and judgment to get the blob just the right amount above of below the set pitch so it sounds right.  You may also want to split the note and only use the drift tool on part of it. 
• Split is funny.  If you don't expand the Melodyne screen to make the blobs larger, you may have trouble splitting.  The split tool is dependent on screen resolution.  In other words, split may not work on a tiny blob until you use the magnifier in Melodyne to make the blobs bigger.  Even then, it may not always split as small a piece as you want.  When you don't think it's working, it may just be because the blob is too small or you are trying to cut off too small a piece.  This frustrates me, too, but it's how it is.
• I transfer the whole vocal at once and then work on it section by section, but that's just me because I am not able to bounce Melodyne very well—something weird about my machine.
• I usually keep ASIO lower—like 64 or 128—until I am ready to do the final mix.
 
You didn't ask this, but if you have any tempo changes, I strongly recommend you transfer the whole vocal into Melodyne all at once so it does not get out of sync.  I have a post somewhere on the Melodyne forum about this because I was having trouble with Melodyne getting out of sync after a tempo change.  If you have a problem with this, I will look for the post and Celemony's answer which was very helpful.
 
Melodyne takes some time to master but it is absolutely awesome once you get it.  You might note that Celemony's videos don't correct things as much as most producers do.  I think that is a public relations thing.

noynekker, I don't seem to have any problems with KA6 and USB3.0. I have had this connected since day 1 this way, and have never had any problems with anything until I started working with melodyne. If I didn't like it so much, I would just quit using it. No internet, wi-fi or anything. I will check the thread scheduling and CPU use.  On the control bar everything looks cool. It doesn't look like I'm using even close to the limits of my system, and yet it behaves exactly like that is the problem. (see rebel007's post above, that describes my situation closely). I am going to try a different approach. I am going to record an acoustic guitar and vocal track only, and fart around with that, and see how far I can push it. I have too many variables in play with this current project (besides, I'm basically done with it, for now at least).
Oh, by the way konradh, I did find all of those tools and took the video "lessons", that's part of the problem, now I'm hooked! I had to fart around with it, and it does some things great, but it's not a magic fix all, you're right. I will report back.  

Great news . . . glad you got Melodyne working better on your system. Cakewalk specifically baked X3 that way with ARA to work inside Sonar, but I guess it still may need some tweaks to work on every type of configuration.