I need help, my system died

My system is only dead emotionally, it still works. Three weeks ago my system was sounding amazing, one of the best i have ever heard. In an attempt to make it even better i tried out some 8 foot cables that are supposed to be better than my current pair. I usually use 20 ft cables and hence i had to move a lot of my equipment to make them fit. Afterwards, i went on vacation and turned off all of my equipment for a week. I also unplugged all of my power cords and brought them with me to try them on my friends system. Its been two weeks since i've been back and my system has easily had enough time to rebreak in as it is always kept powered up. Now, however, although there have been no component changes my system sounds terrible. Well it sounds the same superficially but it seems like all of the warmth, realism and depth have been sucked out of it, while all the detail remains. Does anyone have any idea what could have happened? My system is no longer enjoyable to listen to as it lacks emotion and the rich textures it used to have. Any ideas as to what could have caused this and how to fix it?