Which? Magazine

[Scawby12]

22d) Heirless Bryson eats tip of extravagant river fruit(5)
B?(R?)?Y
23d)Fetch doctor(no time)for person who makes a 10(4)
???F
24a) Combine hydrogen,oxygen and vibrate-it’s not remarkable(2-3)
??-h?m
Possibly ho-hum-but why?

[Lie-in King]

22d Berry - 'Bry(son; heirless)' (eats) 'e(xtravangant; tip) r(iver)'
23d Chef - anag 'fe(t)ch' (no 't[ime]')
24a Ho-hum - 'H(ydrogen) O(xygen) hum (vibrate)'

What was the clue/answer to 10?

[bhg481]

24 H is hydrogen, O is oxygen and hum is vibrate.