Audio (partially) out of sync with video

Hello!
Not long ago I recorded multitrack audio for video. A concert 1hour 30 min long. After I had mixed everything and exported it my audio file became out of sync with video. It is not completely out of sync but some parts of audio doesn’t correspond to video. The difference is in couple of frames.
FPS settings of the project were equal to video (25fps), 48kHz. 24 bit.
Maybe I’m doing something wrong but I can’t figure out what. And because of that my suspicion falls on export process. My guess is that Cubase when exports a file exports it incorrectly.
As a matter of fact it’s not the first time when it happens to me.
Maybe someone is aware of the problem and there are known issues concerning incorrect export? Or maybe someone has any idea what I do wrong.

Thank you!