funny marks in skimming

[ljmetcalfe]

i have recently been getting funny marks in my finish, marks that resemble the sand after the sea has washed over it. i never got these before have they changed board finish and multifinishes ingredient?

 

[Arti]

Sounds like tiger stripes marra. do a search on here cos its been covered a few times

 

[johniosaif]

photos please, is it a grit type mark?