Logic Pro plays wrong notes

Hi BenB, I haven't even recorded anything so no automation has been applied or recorded. By opening an Empty Project with a Software Instrument as the new track and picking a sound from the library and playing from the keyboard the correct note will play at first and then, as I'm playing, the pitch will change without any other control being applied - as if a ghost has changed the mod wheel. The piano roll continues to indicate the note I'm playing but the wrong note comes out of the speaker. I'm reasonable technical but baffled by this.

Hi BenB, I haven't even recorded anything so no automation has been applied or recorded. By opening an Empty Project with a Software Instrument as the new track and picking a sound from the library and playing from the keyboard the correct note will play at first and then, as I'm playing, the pitch will change without any other control being applied - as if a ghost has changed the mod wheel. The piano roll continues to indicate the note I'm playing but the wrong note comes out of the speaker. I'm reasonable technical but baffled by this. It does this on GarageBand too.

Hi BenB, I haven't even recorded anything so no automation has been applied or recorded. By opening an Empty Project with a Software Instrument as the new track and picking a sound from the library and playing from the keyboard the correct note will play at first and then, as I'm playing, the pitch will change without any other control being applied - as if a ghost has changed the pitch wheel. The piano roll continues to indicate the note I'm playing but the wrong note comes out of the speaker. I'm reasonable technical but baffled by this. It does this on GarageBand too.

Thanks for your reply. Both the pitchblende and mod wheel are correctly centred and there's nothing untoward in the event list as far as I can tell.