The phrase "has whack" can be replaced with a variety of synonyms to convey the same meaning. Here are a few options:
1. Has a flaw.
2. Is faulty.
3. Is imperfect.
4. Is amiss.
5. Is off-kilter.
6. Is askew.
7. Is out of sync.
8. Is not quite right.
9. Is flawed.
10. Is defective.
Depending on the context of the sentence, any of these synonyms could be used to replace "has whack" and convey the same meaning. It's important to choose the right word for the right situation to ensure clarity and accuracy in communication.