The basin in DD’s ensuite shower room stinks.
I’ve tried putting down bleach, soda crystals and also one of those sink unblocker twiddly things.
I even had dynorod round but as the water is flowing freely they didn’t do anything.
It used to be our bathroom and it didn’t stink then, but nothing has particularly changed.
It seems to be plumbed in to the main bathroom (which is adjacent) as they sometimes glug sympathetically but the main bathroom basin doesn’t stink.
Any ideas?!