Is there a conceptual influence on plurality according to definable/indefinable number? [duplicate]
Solution 1:
"All" here actually means "The only thing," as in:
The only thing you hear is fear and lies.
So, for me, the original line is better.
*All is singular when used as the subject with a linking verb or when it means the only thing or everything: All I want for Christmas is my two front teeth; all we found was candy wrappers and soda cans.
Solution 2:
The words that precede the verb determine its form, not the words that follow it, so we can disregard the fact that fear and lies is plural. The relevant question is whether all is singular or plural. If it’s singular, the verb is is. If it’s plural, the verb is are. In other contexts there would be no hesitation over making it singular: All I know is that . . ., All that glitters is not gold. There seem to be no grounds for making an exception here, so When all you hear is fear and lies seems above reproach.
Solution 3:
You can use is because 'fear and lies' is one unit of meaning.
In the same way you would say "all he eats is fish and chips", because fish and chips is one meal, or "his favourite drink is gin and tonic" because G&T is one drink.