MARS2 MA501 don't go into sleep

I was having problems with dvd rips on a 50001 v9 PS2 (the games freeze).
And discover that the problem was the MARS2. This chip after boot, don't go into sleep mode, and make the games freeze.
In order to make the games run, i have to install an switch, just like with magic 3.0
http://www.ps2newz.net/forums/showth...t=magic+switch

Definitively, this is not a good work from mars team.

Thanks!