I'm also using a MacBook and Safari. And I get different issues every day. This morning for example, I see html all over the place, posted pictures have been replaced w/ links, I can't quote but I can reply.
FWIW, if it was a problem w/ clearing the cache, wouldn't there be some kind of consistency in the issues? Because for me it is totally random. But it's constant.
As many people w/ as many browser visit other forums w/ issues so I place the blame 100% on Cakewalk. Plus, if they couldn't make a simple forum work due to the variety of configuration, how could they even hope to code a DAW when PCs are all different...