Byte 12 gets set to one when you're in 4 channel mode. Instead of having (the 2 byte) decibel offsets at byte 169 it appears to be at byte 29. Looks like fronts are at 29 and 39, the rears at 34 and 44. I guess this is since if 4 channel is enabled it's only on in car mode.

And it looks like the parameters which would start at byte 229 in the 2 channel case start at byte 89 in the 4 channel case. Front bands start at 89 and 129, rear bands at 109 and 149.

It looks like there are 16 sets of eq parameters, so 16 sectors 2048-2063.

All that should be left for the EQ is figuring out how to calculate the parameter given the Q and "db" settings for each band.