Hi,

There may be a leak somewhere in the system, the noise is normally from a low amount of gas.

Hopefully the porsche centre who regassed the system put a leak detection dye in it to trace the leak.

Look underneath the car on drivers side under the sill area.... There will be two long metal pipes check that they are ot leaking fluid from the front or rear of pipe. Quite a common failure point along with the normal front condensers.

Mike

i'm agreeing with the previous replies, imo it will be low on gas, and you have a small leak somewhere - i would guess condensers as they are what tends to go first - I had the same in mine a couple of months ago, started making a noise, regas stopped it for a while only for it to come back a few days later, traced it to one of the condensers leaking slightly - the aircon guy I used actually sprayed washing up liquid and water mix all over the condensers and we saw it blowing bubbles at the top of the offside condenser.

Thinking I would replace the pair of them whilst I had the PU off, I bought cheap pattern copies and struggled to get them to fit - so much so that I ended up only fitting the one - to replace the leaking one. The mounting brackets on the reproduction condensers were welded so far out of alignment that I struggled to fit one and couldn't get the other one any where near close enough to fit! lesson learnt - stick to the expensive OE parts in the future!