I just unlocked the perk silence for the sneak tree, and it says that I'm not supposed to detected when i sprint, but i still am. Am I doing something wrong?

You still gotta be in sneak mode, before the perk moving fast in sneak mode made you more detectable. now with the perk you can run in sneak mode with no stealth penalty.

You misunderstand it. It has no effect on sprint. It removes the penalty for moving at faster regular paces while sneaking.

You can still be detected by sight, it just makes your sneaking as silent as if you were holding down shift to crawl while in sneak mode.

You still have to be in sneak mode, just while you are moving fast you are just as undetectable as if you were moving slow.

Ah alright thanks everyone, only reason I got it is to finish my tree anyway -.-