Hi,
Thank you, this is what always helps a lot!
A while ago I finally decided to start using expression maps but I had to give up because of this annoyingly inconsistent behaviour. At first I thought I was doing something wrong but soon realised that it was another bug.
I thought expression maps was one of Cubase strong points. 
Crosspost from the other thread mentioned by @beerbong, just to keep things connected. Maybe a mod can merge the threads?
Ok. I tried it. First everything went without problems. But then I thought, what if my system is too fast for this and I built a modificated benchmark with lots of kontakt instances. The more kontakt instances I had, the quicker I ran into problems. I ended up with 120 instances, ymmv depending on buffer settings and system power. So at least in my case it is clearly system spec related. I don’t know if it is more of a RAM issue, or a CPU issue, or whatever. An easy way to trigger the faulty behavior if it doesn’t do it on it’s own is quickly stopping and starting by hitting the spacebar twice while the test is running.
Anyways, here is my project, if you want to try it with an easily scalable test project that is bigger than the one by J Buckingham, but very similar. Just duplicate the tracks (some tracks) if you have a very beefy system or delete some. Requierments: Kontakt w/ factory selection.Dropbox - File Deleted - Simplify your life
Another propably related thing I ran into, when testing some of my bigger projects: sometimes the articulation wouldn’t switch (because it already was on slot 1/default or no articualtion selected at all) but the sound would cut out for a moment on various tracks just to come in a moment later. Clearly something that isn’t happening when on Cubase 10.0. Tried it kinda side to side.
My system specs: Win 10 Pro, i9 9900k, 32GB RAM, NVMe system drive, Samples on external SSD connected via USB 3.1.
Gonna crosspost this to the other big thread, just so it doesn’t get lost.
After waiting a year, it looks like we are going to have to pay Steinberg money for Cubase 11 or 11.5 to get this bug fixed. Not very impressed!. 
Hi,
Ot maybe wait for Cubase 10.5 update.
That’s very encouraging Martin, thanks for the heads up. 
After countless attempts I’m still not able to see, even once, the original bug mentioned here.
However, I am able to reproduce the bug reported by J Buckingham. But no random changes of Expression Maps articulations, and 100% reproducible.
Thus I do not think this is the bug that everyone’s talking about.
Because, first, it’s reproducible in almost all versions of Cubase as far as I can see. And, second, no random occurrence.
If the bug reported by Buckingham is the one everyone is complaining about, fortunately it’s not a big deal!
I am still curious to see a project showing the random behavior described here by other users.
From all the post here I gather that it isn’t actually a random thing but rather a revert to fist slot in the Expression Map thing.
Which when trying to play back a piece of music, sounds very random.
If you are having difficulty reproducing this bug, just add more tracks and try and do more stuff like move the cursor and paste big chunks of data during playback. That should do it.
It’s definitely a processing issue where Cubase is prioritising other things which is when Expression Maps drop their bundle.
Yippee! For Free?
I repeat: I have zero difficulty reproducing “your” bug (I presume Martin too), even with a single track. Totally consistent.
But, again, is this the bug that everyone is pointing here?
Because I see no difference between Cubase 10.5, 10, 9.5, 9.0, 8.5, or 8.0, 7.0 etc. regarding this behavior.
This is the one of the points that puzzles me.
‘This bug’ refers to the bug everyone is talking about, not my bug. But if they fix ‘my bug’ I am confident ‘this bug’ will be fixed.
I really hope so.
But, again, as I wrote, that does not explain why all users in this thread clearly state that reverting back to Cubase 10 solves the problem. This would not be the case.
Anyway, we’ll probably find out soon enough, if there is any change in 10.5.
(To be honest I’m not very confident)
I second this. Was able to reproduce the bug 100% with Spitfire BBCSO and EWHO (which have about 0 similar code between them). The articulations will change to the first slot, no matter the actual written ex.map whenever I start playback while doing something else (moving notes, launching plugins, changing values, etc.). I have about 5-6 tracks running from SSD when that happens, so you don’t even have to go all out for this to happen.
Cubase 10.0.6 - no such thing, everything works as written in the editor.
Hi,
You cannot record this. The internal keyboard of any instrument is never routed to any MIDI Input.
Hi,
Yes, if you are Cubase 10.5 license owner, then all Cubase 10.5.x updates are for free.
Wasn’t that sarcasm? 
I really hope this gets fixed in Cubase 11, but then, why would 10.5 users would have to wait, yet another 3 months to get an update for a stable build we paid for a year ago?.
Steinberg’s attitude towards its users it’s really disappointing and frustrating.
I’m also having this issue. Did anyone come up with a solution?
Hi,
To me, this one looks more like the Key articulation wouldn’t be changed at all. I mean, I can see it changes in the instrument GUI, but the right sample has not been played back.
Can anyone confirm whether this is working properly in Cubase 11 or not?
I would like to update, but I wont if this is still an issue.
I have the feeling it is. But it still isnt with Komplete Kontrol. I will keep you uptodate as Im testing it this afternoon!