VGFacts

I've always noticed this since I first played the game. When you play the songs on different instruments, or on the jukebox in the Extras menu, it plays as normal. However, if you're using the microphone, some of the clips from the song(s) are reused.

The song from (I Can't Get No) Satisfaction by Rolling Stones is one of the biggest examples:

Here's the song when playing different instruments or on the jukebox:
https://m.youtube.com/watch?v=abyqqZNIs7Y

And here's the song when using the microphone:
https://m.youtube.com/watch?v=_CnArk1ktQ0

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Another song that does this is Funky Town:

Here's the song through other methods:
https://m.youtube.com/watch?v=dHahT3ngG08

Now here's the song with the microphone:
https://m.youtube.com/watch?v=Sz4UrUp0eQU

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Another song that does this is Teenager in Love:

The song when you're playing on other instruments, or on the jukebox:
https://m.youtube.com/watch?v=gj9s8w2U77I

And here's the song when using the microphone:
https://m.youtube.com/watch?v=0B8XSW-XZTw


It's likely they do this to lessen strain on the hardware.

Can you point out the point in these songs where the differences can be demonstrated?

Ok!

In Teenager In Love, the singer normally changes voice pitch or exaggerates a little more from one chorus to the next, while being the one in the game remains the same as the first chorus of the song.

The same goes for Satisfaction and Funky Town.