Dontcha just LOVE newbies!?

My latest problem - I use the freebie slideshow (I don't have Premium as I only do one small website for a non-profit group - so, yeah, I'm a total non-professional at this stuff). The photos I drop in are all pre-set (by me) to the exact size of the slideshow box (thanks to a great tip from someone on this Forum), and 72 dpi.

But when the slideshow runs, the photos are noticeably fuzzier and less distinct than the original that I dropped in there. I feel like I have cataracts or something.

So I 'optimized' them all - and that didn't help at all. I turned off the 'Retina' option - and that didn't help. I somehow think that 'optimizing' is the culprit, but I can't find any global switch that automatically optimizes all the photos. I dropped in some new, fresh, non-optimized photos -- and they show up just as blurry as the others.

Any ideas folks?

Thanking you in advance ...