Pink Interlacing

I have observed this anomaly, using 3 different cameras -
Canon's IXUS 40 (SD300), A520 & A610.
Its either vertical or horizontal, happens most of the time in very lightened pictures - but not always. Exposure don't seem to matter.
Anyhow, doesn't look like an optical anomaly...

Examples are attached.

Does anybody have a clue what is this? or how it can be prevented?
Thanx

This is strange. I've never seen anything like this. It's weird that it happens with all 3 cameras.

Can it be the memory card? Is the same memory card being used with all three cameras? Any chance of getting a different / new card and try it out.

James

I wondered if you were using the same card, too. Other than that I can't think of a thing.

Do you have any up-dates about your problem?

James

Thanks guys
But different cards were used.
How memory card type may affect this, anyhow?
The rest 300 pics on the same card were just ok..