I guess whatever parameters there are with movie goofs, excluding stuff thats meant to be false, as in parodies and whatnot.
Two examples:
U2’s “Pride (In the Name of Love)” mentions early morn/April 4th, when the real event happened around dusk I think.
O’Jays “Love Train” mentions telling people in “Africa, Isreal & Egypt”- a bit redundant eh?
Here’s a grammatical example- “Torn Between Two Lovers”- and he knows he can’t possess me/and he knows he never will- should be doesn’t instead of can’t- its repetitive the way it is- but doesn’t is two syllables.
Eric Clapton sings, in “She’s Waiting”
Clearly not what was meant. 
Grammatical issues could use a whole website, but the one that really gets on my nerves because it’s so emphasized is:
“If I WAS to say to you, ‘Girl, we couldn’t get much higher’”
I’m gonna love you
Till the stars fall from the sky for you and I
Doors. (“Touch me”)
DI’s song Richard Hung Himself. 'Your answer is nonseglidur.
James Blunt (rhymes with…) tells us he “a plan” to get this beautiful woman he’s seen. Then immediately tells us he will “never be with [her]”. The so-called plan never surfaces again; there is no exposition. This is one of the many annoying things about that song, not the least of which is that he sings it like he’s got a piece of bread in his mouth.
I believe the same song contains this excessively grating line:
“You know they are a liar”
THEY are A liar? Arg!!
Not the same song–you’re thinking of “L.A. Woman.”
How about Eric Burdon in “Sky Pilot” stumbling over “He’ll stay behind” so it comes out “He stale behind”?
In the song “That’s All,” there’s a line: “A love that time can never destroy.”
Except in Johnny Mathis’ recording, he sings “A love that time can ***only ***destroy.”
I can’t believe nobody in the recording process caught that.
Especially since a perfectly acceptable alternative would be
’til the stars fall to the sea, for you and me.
It’s the singular they. It’s been around since the Canterbury Tales.
Any song using “you and me” in place of “you and I”. Or vice versa.
Yeah, well, talk about goofs. The spelling in that thing!
“If I was” is colloquial and the English subjunctive “if I were” construction seems to be disappearing in all but the most formal of speeches. I have noticed, though, that “if I was” seems to be more acceptable across the pond than in the US. (Not that it matters in the Doors case).
Thank god grammarian’s don’t write songs, else we’d have such classics like “(I Can’t Get Any) Satisfaction” and “There Isn’t Any Sunshine When She’s Gone.”
In “City of Dreams”, the Talking Heads sang “From Germany and Europe”. Really? Both places?
You’ve inspired me to start a thread on the subject. 
A little obscure, but: Billy Joel, “Souvenir”:
"And your momentos / Will turn to dust . . ."
Ruins one of my favorite songs just a little bit. When I sing it, I use the correct pronouncination.
How about this one from A Man for All Seasons by Al Stewart.
Henry Plantagenet still looks for someone
To bring good news in his hour of doubt
While Thomas More waits in the Tower of London
Watching the sands running out
I’m honored. I can’t believe I spelled “grammarian’s” with an apostrophe. :smack: