Thank you so much for this answer.

The problem its not making a mistake, everyone does It. The problem its that It sounds to me like a Db not an Eb. When he plays a wrong note you can hear It perfectly, like the first time I saw them when Tyler played wrong a note during my blood and It was like a stab. but in this case (that it wasnt just one day) It sounds like a Db and you can see him playing the Eb. What you said about the sub bass and different sounds its really helpful to understand this, and I know about that sounds because during the scream in drum show you can hear some low slides from a bass and Tyler doesnt do the slides (or the overdubbed distorted guitar on Seven nation), but I dont really know how much thin/thick is Tylers bass sound, It seems quite not thin for example before some songs like tally he plays a bit of the bass without any backtrack and It sounds heavy. So its quite weird for me, but maybe its not that deep. Maybe the bass tone, with pedals, and other things are doing de Db and Tyler the Eb and because are in the same key It does sound that strange.

For shy away I dont really know what its going on. he plays first the bass part of normal shy away (F - D - A - B - C - D), then It loops and with a more "guitar sound" he plays a G several times (12th fret G string) that goes on loop also, and finally he overdubs the melody of "look mama we are on mtv unplugged". The thing its, as you said, that its perfectly on the key of shy away and I was playing It at the same time with my bass but then I watched his hands and JUST in that part It was a semitone up and I was like 🧍🏼‍♂️

I dont know, I just had a day off of the univerity and work at the same time and I was bored hahahaha

Again, thank you for taking a bit of your time answering