I once had a 2 meter pair of Nordost SPM interconnects cut in two and reterminated by Nordost into two 1 meter pairs. One pair sounded about the same as before, but the second pair needed almost a month of constant playing before they sounded like the other pair (more harsh at first). I concluded burn-in of cables may be from one end to the other, so one half was still burned in, the other like new.