rear axle pressure

after finding oil seeping from my rear hub, I suspected a blocked breather pipe. This was confirmed, when I removed the axle level plug and I heard a "pshhshshsshsh" sound.the thing is, they are remote breathers which means the only way the breather can become blocked is if the pipe is blocked or squashed.
so what is the proccess for ensuring the remote breather pipes are clear?

Remove and blow thru them