Thanks for all your suggestions, I tried everything including turning off the Wifi (this is a desktop, but it has wifi and I disabled it), and all the rest. Nothing worked. So I switched all the settings back to the way I had them.
I noticed just now that one delay that I hadn't tried yet with the new PC doesn't have the same problem. It's an oldie but goodie: the Sonitusfx Delay.
I never really use it, but I just tried it... and it works. No clicks/pops, etc. I have been using the Cakewalk Tempo Delay recently, but now that I know this one works for me...it's great! I don't know why it would make a difference, but if it works.. it works. Weird...oh well.
When i get a real audio interface, I am sure any problems like this will melt away and should be gone, but I just wanted to work on a few things till then. I hopefully only have to wait a few more weeks, and then can also buy a few other things, like a new keyboard, and new monitors as well.
Thanks again,
-Rob