I've had similar issues, one was solved with a new bottle the other still leaks with a new bottle even when it's left unused, left in cupboard above the cooker so I did put that down to the heat expansion.
Now there's one of my Pulses I can't stop leaking, brand new bottle, pushes all the way up, all fine while using it, put it down only to find a pool of juice the next day - mystery to me as unless there's a vacuum in the bottle it's defying gravity and I can't pinpoint the leak.
I did try to strip the whole thing down but the switch is soldered.
Hopefully someone has an answer.