Related Clues:
- Sounds off, possibly, in the theatre
- Scrapes fruit briefly
- Sounds like a couple of rackets?
- Bumps in the night
- - - Off (stage farce)
- Starts to roughly apply sand paper, say
- Grates harshly
- Knocks receiving small scrapes
- Head of school involved in knocks and scrapes
- Bangs, yells, sirens, etc
- Rough metal files
- Talks with a very sore throat
- Malfunction indicators, perhaps
- Introduction to Shark, found in upended box files
- Poltergeist's output