belt squealing diagnosis

[speed_krazy_chu]

My car squeals after driving after i drive for a couple of minutes and higher rpms. I have an unorthodox UDP and just had to get a new alternator because my last one died on me. Once i got the alt on and i put on the belt it did the same squealing but was alot worse and wound up snapping off. This one only goes on after driving a couple of minutes after i warm the car up for like 5-7 minutes. When i have my sound system and other electronics on it squeals alot more. Could it be my alt. is not putting out enough...putting out too much. The 2nd belt was done professionally by a shop cuz it was like 100 miles from my house in the middle of no where. please help!Thanks

 

[Mike1992]

Tighten the tensioner its loose

 

[Rx3]

Tighten the tensioner its loose

 

[speed_krazy_chu]

i did that last time and it didnt get any tighter,and the dumbasses @the shop seemed to put on a SAE bolt on the lock bolt...it seems to be 1/4" now...