if the stock is tied in airtight, the only other variable is the hole in the stock where you plug the chanter in. If this is a larger diameter or different shape, you may be getting leaks from there. Some stock holes are tapered, others straight bore. I personally prefer tapered as I found you don’t have to be as precise with the wrapping on the chanter.
Also double check your reeds are snug in their seats. Last time I tied in a new bag (which was quite recently), I had a drone reed come loose inside the stock.
Some stock holes are tapered, others straight bore. I personally prefer tapered as I found you don’t have to be as precise with the wrapping on the chanter.
A slight taper widening towards the end of the stock is best as it allows for wood shrinkage and have come across this on several historical sets. Wood shrinks when it looses moisture and this is fastest at the exposed end grain causing a parallel bored socket to become a slight taper narrowing towards the end of the main and other stocks which can make wrapping difficult to get a secure fit or more likely to leak.
We are now into a soggy autumn so have the reeds opened up or stiffened, are the reeds seated properly, are the pipes secure in their sockets, have you tried plugging the stocks to check none of the tie ins or bag itself is leaking, are bellows tight and valves sealing properly ?