Serpentine belt squeak

Hey guys, this is my first post. and I got a question about an 08 Tacoma with the 4.0 V6 in it. It has a bad serpentine belt squeak that I have not been able to track down. I’ve used the water trick spraying it on The Pulleys and the belt and I cannot find where it’s coming from to preface all of this I have replaced the power steering pump all of the idler pulleys the tensioner pulley the alternator and the AC compressor and have tried four different serpentine belts and I still get a squeak mostly whenever it rains and is really humid or hot in Iowa. However, it doesn’t make noise when the belt is wet I had it to a shop and the only thing they could tell me was that the factory belt was slightly too long and to try a shorter belt, which i did and it solved the problem for three days and then the squeak came back when it rained overnight and has not quit squeaking off and on since

 

Weak tensioner perhaps? If a slightly shorter belt helped Id think it was due to the increased tension

Of course you can partially remove the belt and spin most of the pulleys by hand. See how they all feel

 

Yes, I thought of that. Replaced the old tensioner with a new one thought that it wasn’t giving proper attention so I bought a better one and replaced it with another new one all of the Idler pulleys And the alternator have been replaced twice just because I wasn’t sure if the Idler pulleys I had bought were cheap for what so I replaced those again and the first alternator was defective actually ripping up the belt

 

Aftermarket or OEM replacement parts? You probably know where I'm going with this.