apple tv 4.1 - 8c150 - jailbreak failed


A friend sold me one apple tv second generation, black that he did not used.  

It has the firmware 4.1 in About.

I managed to get the blobs with iFaith: 000000168106A5CE_Apple_TV_2-4.2_(8C150)-blobs

Now, I am interested in jailbreak and xmbc but failed to get it working. Tried lots of combinations, restore ipsw, signed (all failed with 1600 error despite the iRED enabled with that deep recovery thingy), jailbreak with limera1n, snowwhatever, all of them, none succeded. 

Last one, last night, with GreenP0ison RC6. Which goes fine, jailbreak done but when booting up the appletv it gets stuck after the apple logo is displayed, no signal to tv.

Anyone can help, how can i jailbreak untethered the damn thing?

Can i upgrade to 4.4.4 without blobs and have untethered? Or 4.3 or 4.2 or a better one than this i got?

Thanks in advance