Why is "are you listening to it?" wrong? isn't słyszeć both hear and listen like its Russian counterpart слушать?
'listen to' = 'słuchać'
'hear' = 'słyszeć'
"Are you listening to it?" would be "Słuchasz tego?".
You need an accusative form of the pronoun 'to', which is simply 'to'. 'Czy słyszysz tego' is therefore incorrect.
You can construct a sentence where 'to' would appear in genitive case 'tego', e.g. 'Czy nie słyszysz tego?' - 'Don't you hear it?'