Freelander V6 low power and misfire
 

I have a V6 2005 Freelander with 170,000kms on it. Sudden loss of power and misfiring. I've pulled the codes as follows;

P0305 Cylinder 5 misfire
P0306 Cylinder 6 misfire
P0032 H02S Heater control circuit high bank 1 sensor 1
P0442 Evap System leak (small leak)
P1477 Unknown
P1474 Unknown
P1472 Unknown
P1471 Unknown

Does anyone know where I should start looking or what the likely culprit is for this particular combination of codes?

Thanks in advance