[solved]Strange "glue" behavior

On a midi trak i have a region with some midi events. then i add new totaly empty region on the same trak using “draw” command BEFORE the region with the midi events. so i have 2 parts : 1st part empty, 2nd part with some midi events.
Then i select both parts and tap the “glue” button. both regions are now gued to one bigger region. so far so good.
BUT: in the 1st part, that was totally empty before , there apreares magicaly now some additional midi events, obviosely copied from the 2nd part. i don’t want that.
Is this a bug , or some strange feature, that i don’t understand ?

Found the answer for myself:
you record e.g. from mesure 3 -4 and accidently hit one ore more keys before the mesure 3 actually starts. if the “record mode” was set to “count” or “roll”, then the Cubasis records these key events also, but you will not see it.
To make them visible you need to drag the start of the recorded region to the left. now you can see the events. to get rid of those events, just split the region and delete the part befor mesure 3 start. now you can add and glue other regions before without the side effects described above.