setTimeout and QuickTabs
Alright, the problem was just plain old Javascript.

The bug made it look like the setTimeout had no delay parameter, which defaults to 0.

After looking more at it, the rotateSpeed variable was not available in the block scope of the featureRotate function, but in its closure.

So I replaced the following:

// In the featureRotate function
setTimeout(featureRotate, rotateSpeed)


With:

// In the featureRotate function
setTimeout(featureRotate, this.rotateSpeed) // Look at this magic :-)


And it works perfectly!