The digital lounge room is where PC and AV merge, but unfortunately the two tend not to get along.
While interference on analogue television tends to introduce ghosting and fuzz, interference on digital television tends to cause parts of the picture to pixelate.
Serious interference can see the picture freeze completely for a few seconds, a less than satisfactory experience when you're watching live sport.
When it comes to sources of lounge room interference, major offenders include AC power packets, wireless networking equipment, cordless phones and VoIP adaptors. Placing these devices within a few metres of your television, digital receiver or aerial cables can result in significant digital interference.
Running aerial cables close to your electrical wiring, or using the power points alongside your aerial socket, can also introduce signal interference. Interference can be intermittent and restricted to certain channels, so the source can be difficult to pinpoint.
Along with moving PC and networking equipment further away from your AV gear, you can also reduce interference by using RG-6 shielded aerial cables with screw-in F connectors rather than cheap aerial leads.
You should also remove unnecessary splitters or consider using powered splitters rather than passive.
If problems continue, you'll find DTV Forum Australia an invaluable resource for trouble-shooting advice.
Also in this series, Picking the Perfect Home Entertainment Box:
Part 5: Do you need a Freeview sticker?
Part 4: What's the best way to record your favourite shows?
Part 3: networking your TV, PVR, console, set top box
Part 2: creating a P2P season pass
Part 1: Internet video on the PS3
Buying a TV? Also see our series How to Pick a Great Flat Screen TV, And Not Get Sucked In By Marketing Hype