I have similar experiences with my Au24's and jumpers. The only problem with mine were that the Au24 jumpers with banana terminations were not as solid a connection as I would prefer.
So I re-installed the stock jumpers along with the Au24 jumpers and noticed a substantial improvement still.
Recently I removed the stock jumpers and am now using some better terminated bananas for what so far appears to be better sonics still.
Spreading the little cleaning juice that comes with the cables on all connections also helps quite a bit.
I thoroughly enjoy the Au24 cables.
-IMO
So I re-installed the stock jumpers along with the Au24 jumpers and noticed a substantial improvement still.
Recently I removed the stock jumpers and am now using some better terminated bananas for what so far appears to be better sonics still.
Spreading the little cleaning juice that comes with the cables on all connections also helps quite a bit.
I thoroughly enjoy the Au24 cables.
-IMO