Beat Grid is unreliable

Hi there, I seem to have a problem with the beat Grid.

Firstly, Serato seems to always recognize fast tracks at half their bpm. So tracks with a bpm of 140 are reliably labeled as 70bpm for some reason.

And secondly, sometimes the beat grid doesn't align with the audio at all. So if that happens, beat sync is completely broken and I have to manually align the grid with the downbeat.

Is this normal? And what could cause this? Is there to fix it without having to manually check and edit the grid of my entire library?