The most common and most likely answer to this crossword clue is the 7 letter word DISTURB
I've seen this crossword clue in The Guardian
D
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S
T
U
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B
More clues leading to the result DISTURB
- Dry fellow rising to interrupt
- Man turned right in Bath, finding trouble
- Interrupt attempt, including routines set up
- Insult curt swine brought up creates upset
- Upset sub, dirt flying
- Ultimately joyless sex in retirement, tender embraces from behind prove unsettling
- Girl’s cologne knocked over? Bother!
- Upset by rejection of offer to contain rust problem
- Unsettle dicky birds round bath briefly
- Upset, try covering tracks up
Buddy explains!

The straight part
We know that "prove unsettling" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case prove unsettling = disturb.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 DISTURB mean?
DISTURB noun- Disturbance
- To confuse a quiet, constant state or a calm, continuous flow, in particular: thoughts, actions or liquids.
- To divert, redirect, or alter by disturbing.
- To have a negative emotional impact; to cause emotional distress or confusion.