Thought I would write and let others know in case they ever have the same type of creaking noises.
We found out what was causing our noise. It was a wall tie which had not been put in with the correct type of screw. The actual tie was solid. We cut the tie and we have had silence ever since - absolute heaven.
We isolated it ourselves which took some time but well worth the time we spent with our ears to the wall trying to pinpoint.