V-belt quality

[Peter Orban]

Hello Everyone,

Happy New Year to Everyone!

Question about V-belt quality, the make I have been using keeps stretching.
The V-belt in question is the Continental AVX10X950 (my apologies, it is on a VW Golf ;-). It has the V notches and the reinforcing belts are only at the outer edge. 

My son lost the previous belt, it was a bit loose, it started screeching occasionally around 3K RPM. We kept tightening the belt, about every two month or so. 

Now I put on a new belt, also the same Continental make. It was tight when I put it on, and now, a couple of days later it is not so tight.
Is that normal? I don't think so!

Thanks, Peter