the changing sound of compoents over time

i have noticed changes in the sound of my stereo system, which i would not attribute to changes in the AC.

these changes are not temporary, as one might expect from changes in voltage, current, or others brought about by the actions of a local utility or increased current draw of a seasonal nature.

i am referring to the affects of oxidation and the degradation of solder connections.

i had an experience with cardas cables, which i would not attribute to a change of a temporary nature.

i had been using cardas golden hex 5 c interconnects, speaker cable, golden line cords, twin link interconnects and golden cross interconnects for at least 4 years.

these cables allegedly have a reputation for a "soft" treble response.

one day i was listening to my stereo system and i noticed a marked change in the highs.

this change continued for months. one day i decided to sell the cables.

this phenomenon was unsettling to me because i could not pin point the reason for the change in the sound i was experiencing.

i had a similar experience with a line cord, where several months after break in , i believe the "sound" of the line cord changed for no apparent reason. my friend suggested that cables ultimately "return" to a neutral presentation after some period of time, regardless of their sound after break-in. he said it had something to do with the dielectric material.

any thoughts on this subject ?