Would appreciate help. I cannot view Google maps properly - I tend to end up with diagonal 'blocks' of image across the viewing area, like a really annoying checkerboard. It happens in both Firefox AND Safari (I am running Mac OS 10.4.

.
I have tried clearing the cache in both browsers but the problem persists.
I also have a now defunct Windows PC upstairs, and I get the same problem using IE, so I am completely baffled. Does this mean it must be an issue with by ISP? (which is BT in the UK by the way.)
Thanks.