The most common and most likely answer to this crossword clue is the 10 letter word MOUTHPIECE
I've seen this crossword clue in The Times
M
O
U
T
H
P
I
E
C
E
Buddy explains!

The straight part
We know that "Spokesperson/bit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case spokesperson/bit = mouthpiece.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 MOUTHPIECE mean?
MOUTHPIECE noun- A part of any device that functions in or near the mouth, especially:
- A spokesman; one who speaks on behalf of someone else.
- A lawyer for the defense.