Doesn't seem to have any wear, is it a fairly new chain? Only small ring / large cog, no other cog / ring combination? Axle is fully seated in the drop-outs?
Is the top of pulley making contact with the bottom of cog or are they trying to overlap, say side of pulley to side of cog contact? I was thinking maybe you could try adding a link to the chain, but it would seem the problem would occur in some big ring selections too if that was the cure.
If that doesn't help, stay out of the granny combo and evertything will be fine
2003 Iceman Challenge - 2:34:55 - 897 / 2,000*
2002 Iceman Challenge - 2:39:23 - 1093 / 2,186
2000 Iceman Challenge - 2:49:18 - 1516 / 2,153