The most common and most likely answer to this crossword clue is the 7 letter word RAPPING
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Buddy explains!

The straight part
We know that "hip-hop performance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hip-hop performance = rapping.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RAPPING mean?
RAPPING verb- To strike something sharply with one's knuckles; knock.
- To strike with a quick blow; to knock on.
- To free (a pattern) in a mould by light blows on the pattern, so as to facilitate its removal.
- To speak (lyrics) in the style of rap music.
- To talk casually; to engage in conversation.
- To seize and carry off.
- To transport out of oneself; to affect with rapture.
- The sound of a rap or knock.
- Musical speech accompanied by a rhythm, most commonly as part of hip-hop music.
- Remarkably large; whopping.