Is it not more likely that it's just a general accumulation crap? Of course, you'd know better than me whether you're living in some sort of rodent-infested ghetto. :-P In my experience, it's more likely to be a built up of bits of food and tea leaves and other assorted rubbish. As soon as the gas hits the blockage, it'll break up and wash away. That's my tuppence worth...
Is it not more likely that it's just a general accumulation crap? Of course, you'd know better than me whether you're living in some sort of rodent-infested ghetto. :-P In my experience, it's more likely to be a built up of bits of food and tea leaves and other assorted rubbish. As soon as the gas hits the blockage, it'll break up and wash away. That's my tuppence worth...