Hi all, I'm hearing a slight blow off sound when backing, running original plastic dump valve, is this normal or have I a leaky hose somewhere????

Its normal some OEM valves are louder than others, mine was as loud as another members Forge 007 on her 4x4 1.8T, both on the standard airbox. If you have replaced the OEM air filter with a performance once you'll be able to hear it a bit more clearly too.

Ok no probs, could you suggest a filter to buy, many thanks

If you're just replacing the panel filter the three main ones are piperX, K&N or Green.

They're all between £30 and £50