Uuuuuuuuum…well, I learned two things just now. :o
I believe you, because that’s how I used to sing along to it in the car, and still do in my head (even though I know better).
“Cheerleader” by OMI -
Real lyric: “But I’m empty when you’re gone”
I hear: “But I’m deep in your corner” or “But I’m deep in your arms”.
“Some Kind of Wonderful” by Sky:
Real lyric: “She makes a mean steak and she’s an eyeful”
I hear: “She makes a meat steak by the lamp post”.
Life Is A Rock
Lyrics: ‘Life is a rock, but the radio rolled me’
Misheard: ‘Top is a rock, and the radio told me’
I blame the Radio Shack AM radio on my bike’s handlebars.
I heard “mama don’t take my corn pone away.”
Todd Rundgren/Utopia: “Sunburst Finish.” I couldn’t quite grok Kasim Sulton’s pronunciation of “Foxy pharaoh knows all, won’t tell” but I was sure it couldn’t possibly be what I kept hearing:
Fozzie Bear, ah! Knows all, won’t tell…
“Blinded by the Light” by Manfred Mann
lyrics:
Blinded by the light,
revved up like a deuce,
another runner in the night
misheard:
Blinded by the light,
wrecked up like a douche
I know a runner in the night
I hear “Wrapped up like a douche”.
Another classic is “Going down on the old man with a transister radio.”
For years I thought the Jimmy Eat World song “Lucky Denver Mint” was called “Lucky Tenderness.” If I hadn’t tried to look up the lyrics one day I’d still be wrong.
A more obscure song from the O’Jays album “Ship Ahoy”
“Oh, baby, I guess you’ve got your hooks in me
And I’m caught like a fish”
This was one of my favorite songs. I always sang along “and I fought like a bitch!”
Same here. I was wondering why they were singing about an obscure TV hero with Sid Melton as a sidekick.
Jane’s Addiction - “Just Because”
Actual lyrics:
When we first met
And we passed around gifts
For some reason, I heard it as
When we first met
And we passed around fluids
I figured he was talking about sex.
This is what I heard.
Also,
Hey Lawdy Mama** by Steppenwolf
Correct:
It’s alright, Hey Lawdy Mama.
I heard:
It’s alright, day or ni-ight.
They actually re-recorded the open at some point with Jean Stapleton over-enunciating those words.
M & Ms Front…
M & Ms Front…
It’s a put on.
How do you know what the official lyrics are?
I don’t, unless I have direct access to the original ones printed on the liner notes.
But many bands never released any official ones at all. Which means that it was nothing more than some internet junkies somewhere guesstimating them, full stop. And then shamelessly copied from each other. So much so that, just because lyric sites 1-10 all say the same thing, and I hear another (still 100% convinced I am right about the Pearl Jam one above), doesn’t mean that I am wrong, and they are right.
I’ve seen quite a few glaring errors, where there is no way that the singer is singing what these sites insist they are singing (extra syllables, missing consonant sounds, etc.).
So how do you know for sure what the right ones are?
The Cisco Kid
lyric: Eat the salted peanuts out the can
I heard: He has the softest penis in the land
For some reason, this one popped into my head a few times over the past week; and last night I saw The Full Monty for the first time. I’m going to blame my Archer AM bike radio again, for my mishearing the lyrics. 
You Sexy Thing (aka I Believe In Miracles) by Hot Chocolate.
Lyrics:
I believe in miracles
Since you came along
You sexy thing
Misheard:
I believe in *Milkos
It’s a kind of law
You sense the pain
*‘Milkos’ sounded like some sort of breakfast cereal.
On the way home from work last night I heard/remembered another one…
The Marshall Tucker Band’s “Heard It In A Love Song”: as a kid I always thought they were singing “purty little love song.”
(For those outside the USA: “purty” = southern slang for “pretty”)