How come I can't get sound with Hulu, when I do get sound on my computer otherwise?

Are you getting sound from other browser based stuff like youtube.com?

And what browser and operating system are you using?

Yes, seem to get sound from other places. Just not hulu.

What I would do next is try it in another browser. If you are using IE try Firefox or Safari

If it doesn’t work in those then you might need to try reinstalling Flash.

Yes, upgrading to the newest version of flash is your best bet. This also fixes some YouTube problems when it says a video is unavailable.