A recent patch note said that Stealthy was changed from +2/+2 to +3/+3. Unless my math is off, it's still only giving me +2/+2.
it seems to fall under reset perk, if you do that it should fix it. If not relogging then applying the reset will give you back the stealth.
Especially if you log in for the first time post reset
Yup, that worked! Thanks, RWG.
Sorry for the unneeded bug report.