Why in Rocksmith score attack, even I got 100% and platinum pick, I'm not in first place?

I'm trying to be 1st place in leaderboards in Score Attack for the song Have You Ever Seen The Rain from CCW.

I have achieved to have 100% of the song and got platinum pick and I'm still in 9th place.

The multiplier can't be the problem, since I have made all single notes correctly.

What other variables are giving those people ahead me more points?

The multiplier or score is affected for Perfect Phrases?

Thanks!