The most common and most likely answer to this crossword clue is the 10 letter word SOUNDCHECK
I've seen this crossword clue in Financial Times
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Buddy explains!
The straight part
We know that "In which techie aims to get his level best" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in which techie aims to get his level best = soundcheck.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 SOUNDCHECK mean?
SOUNDCHECK noun- An activity that takes place before a concert, etc., when the performer and sound crew run through a small portion of the upcoming show on the venue's sound system to verify the volume and tonal frequencies.