Laptop DV6 won't turn off!

[Alfre.cuba]

Hi everybody. Maybe this is not the place to post my problem, but since there is a lot of smart people here I'll taking my chances. I have a problem with my DV6-6167la laptop: it won't shut off. I go to shut down Windows normally, screen goes black, looks like it's turning off, but the power stays on... leds and fans. Even if I long press the power button stays on. Only unplugging the AC and removing the battery gets completely off. Its the same with Windows 7, Windows 8, Linux, even without hard drive and booting form USB flash drive. I already remove the CMOS battery, upgrade the BIOS, in fact I am using now a modified version of F.1b Insyde BIOS in order to unlock the energy options, but nothing seems to make the system shuts down totally. Anyone has any suggestions that can fix or an explanation to why it's doing this? Thanks