i know its a stupid suggestion , but you do have it switched to bank 1 for v1.6(im assuming the white cromwell edition is the same as the blue one with 2 banks)? , other than that recheck your lpc wiring , altho it sounds like it could be a cromwell incompatibility with your 1.6 but i really aint sure
also im sure i read thatsome people have probs with a/v leads other than the one you get with xbox , again not 100% sure tho
**edit** oops sorry just done some reading on the white duox , i was wrong , it dont matter what bank you use , sorry i would still try bank 1 tho