KM Z5 lag?

[marcoj]

hi there

i've got a z5 for about a year and i simply love it for pictures. i mean, its not "perfect" but for the price is way above average

yes it has its bugs on video mode (2 "dead" pixels and that anoying autofocus noise while recording video) but what's really buggin' me is one detail... when i record long videos (long.. 4 mins or more ) the sound starts to be desynchronized with the image.. it starts to have some lag. why does that happen? can it be because of the 1g sd card? has anyone experienced that before?

thanks