Battery drain problem

[Stava]

Any help would be appreciated.
The battery on my 04 3.0d has been going flat if left for more than 24hrs. I have checked all the fuses one by one and found that if I pull the radio fuse (in the boot) the drain drops from 450mA to 40mA when the car is in sleep mode.What do I do next to fix the problem? With the fuse out everything works except for sound, so no radio/cd/television/phone. Can't leave it like this for long!

Don't know if its related but the tv was modded by a previous owner so it can be on while driving. Also there is message; 'check number plate light' but lights are OK.