Audio synchronization is VERY SLOW

Hello,
Lately, when I use the synchronization tool on Premiere Pro (right clip on the selected audio lip > synchronize), it's very slow. I mean, it took at least 10 minutes. It used to be just few seconds.



Maybe I've changed something in my settings that I'm not aware of... 


Has anyone rune into the same problem and has the solution please? 

Thank You