Watch again this week. It was definitely noticible on Monday’s episode, and no it’s not my TV signal, I’m watching on CBS.com!
At least from my experience, the CBS.com stream isn’t exactly flawless. Unless something has changed recently, the streams are 1) compressed to something that’s still “HD” but not as crisp as the TV broadcast and 2) displayed at 30fps rather than the correct 59.94i frame rate it airs at, which, combined with the compression techniques used, makes things a bit jittery, for lack of a better term. I would say If there was one part of the show where this would be especially noticeable alongside the audio sync is during the Showcase Showdowns, and that seems to be what you’re experiencing.
Then again, I haven’t watched a recent broadcast of the show, so I can’t speak for any differences y’all are seeing other than what I’ve noticed before.