When your Gamecube loads up and the bouncing square makes the "G" hold "Z" and you'll hear some weird noises

Plug four control pads into ure gamecube and hold Z on all of them while switching ure gamecube on and youll hear jungle noises! pretty cool!
Doesn't work 4 me- maybe 'cause I've got the platinum 'cube...
I shudnt have thought that wud have anything 2 do with it! if so, its very strange!
I've tried everything. Just can't get it to work- explain how you do it...???
Just hold down the 'Z' button on ure Gamecube controller, while turning it on, and keep it held down until the moment the logo starts to appear and makes the funny kiddy noises! Then let go when its finished! Simple....supposedly!
The problem isn't the platinum coulour...