This has been an issue since the first snapshots of 1.8. It still has not been fixed so I decided to report it. When ever I have command blocks giving effects, it give one extra level that I want it to. If I do /effect @a 1 30 1 true in a command block, it will give all players speedness level two. If I do /effect @a 30, it will not give an extra effect, it will just give Speedness level 1, but I don't want it with bubbles. This has become very annoying. Please fix this bug.