Hi, had all the same symptoms as many on here so decided to sort my H3 as Saris still haven’t answered my emails.
As many the sounds the trainer was making I thought I would fall apart.
So, I’m in the UK so need to ensure you have imperial Allen keys as the smaller screws that hold the cover on are NOT metric. If you’ve got the cover off the 2 areas I identified as faulty are the large plastic fan pulley and the black ribbed (small) pulley as many have mentioned
1st remove the tensioner and I inspected the black ribbed (small) pulley. The Philips screw that holds it on is not worthy. Remove this and replace this with a bolt or Allen key head bolt. The ribbed pulley DOESN’T fit well on the spindle so the tension in the bolt securing it is vital. I believe this is where the clicking/ knocking comes from!!
I used tread lock and fitted a locking washer (looks like a washer that been cut and twisted) for those not familiar. The bolt I used was twice the length of the pathetic one that was fitted. The bolt head allowed me to get a lot more torque on the pulley so all play was removed.
Next I removed the upper plastic pulley . I used a soldering iron and etch grooves horizontally all the way around the contact area. I’ve attached a pic. Made sure the 3 bolts holding the tension plate were tight and then reapplied the tensioner to a 19mm gap.
Used some pulley belt spray to prevent slipping. Tested it today, not a squeak, click or clonk