[delicado]

I've been a Notation user for many years, Musician first, later I switched to Composer. A while ago I upgraded my Composer to version 2.6 (I don't recall what my previous version was). Later I noticed that transcribing guitar chords works quite different than it used to. First it takes much longer than before (several seconds), it used to take less than one second. That's not really an issue but unfortunately the result is not correct from time to time. Wrong chords may be displayed and the chord change may be at the wrong time, displaced by one note or even half a measure.
In order to find out what goes wrong I've erased all other instruments but the guitar - the result was as wrong as before anyway. Beyond my understanding - you can see the correct notes and the wrong chord name in corresponding locations at the same time!
Now I gave Composer 3 a try: Chord transcription works the same way as in Composer 2.6 - not correct.
Can anybody help?