hi guys, i have been reading allot online on this problem but i never found an answer that works. also most people described their problem a bit differently than what is happening to me so here it goes:
 
i use cubase 5. i am using the studio instruments vst.
i have been using this product with this daw for a few years now. i used it on many songs i recorded and everything worked fine.
for some reason the other day i pressed the play button of my cubase daw and the vst played the notes without ever stopping them so as you can imagine all the notes were played together as a big mess.
i read in many places that the problem is that the daw does not send the note off to the vst. well 2 things: 1 - it does not seem to be the case as i see the little light (a cubase feature) turn red at note on and a few sec later (i am guessing it is the note off) but the note keeps on playing (until i press the stop button on the vst it self) 2- if this is a case of note off, how the hell do i fix this in cubase 5? i really like this vst and i don't know what to do anymore.
i tried re installing the daw, i tried re installing the vst, i tried re installing both. i tried deleting newer software from the computer that might be clashing with this vst. i really do not know what to do anymore.
your help ASAP would be greatly appreciated.

 
Welcome yubalito,
 
Are you in any way related to a user by the name of NewRoch ?  S/he had exactly the same problem just three weeks ago, but apparently on Cubase 6 (or 6.5).  See this thread and this thread.  Your english is quite a bit better so I'll presume you're different people.
 
There is one known issue :  Notes may stick while playing patterns and looping in your host.
 
If this is not your problem, then something seems to have changed either on the Cubase side or on Cakewalk's.  But Cubase 5 & 6 are old and Studio Instruments are ancient, so it's unlikely that these programs have changed.  Does Cubase still offer patches to versions 5 and 6 ?  Or maybe you both switched to Windows 8 or something ?
 
I suggest you contact Cakewalk support or call them even if apparently they no longer support Studio Instruments.  If you two have the same problem you can't be alone so maybe they've received other requests and may have some ideas.

hi. well i am not the same person...
to be honest this . is not exactlly what my problem is because i am not using and patterns that come with the vst.. i am playing my own notes.
this is really weird. i just installed cubase and the vst on a never before used computer (i mean this computer never had these programs in it) and it is running windows xp (just in case) and the same issue happens. it is driving me nuts... i did use this plugin a few weeks ago without any problem.

I just did a quick search of these forums and discovered that this problem has been around for a while.  But you say it was working a short time ago ?  That's promising, but you'll have to figure out what you did to change things.
 
Using the following search command without the square brackets  (the forum search is broken)
 
  [ notes sticking cubase "studio instruments" site:cakewalk.com ]
 
I found several similar issues, for instance here, and here  (it's worth reading all of the threads of these messages)
 
It would be worthwhile to see what midi codes are being sent.  For example, here's a message dealing with NoteOff and AllNotesOff.
 

Make sure you don't have a stray sustain on cc in your midi clip. That will cause exactly what you're dealing with.

Still happening in 2018. And no Cakewalk support. Or was there ever on this thread?

This is a user forum. In 2015, the advice to contact Cakewalk support was a good one. Unfortunately the OP never returned to report what support had to say (assuming they were contacted)

I just encountered the problem previously and the only way I found to stop it was to click the Reset MIDI and Audio button in the Transport module.
 
See the Cakewalk Knowledge Base.   Hanging Midi Notes