I had the same problem with D5, i.e. washed out sound. However I also use what used to be called Deoxit Gold ( the company seems to be changing the names) and that was quite the opposite, i.e a big improvement in sound quality. As I understand it the D5 is a straight cleaning fluid, the Gold is a cleaner plus a contact enhancer presumably it adds in some kind of fluid which is conductive. Possibly what we both found was that clean contacts don’t actually sound that good or the D5 leaves some kind of film. Irrespective, I just added an application of Gold and was very happy.
Treated my interconnects with Deoxit D5 today
I have a nice audio system and had a great notion to clean all my connections with alcohol and treat all the connections with Deoxit D5. I did all the fuses as well. Well, the result is that the system now sounds flat and lifeless as hell... way different than I previously heard. What's up with this? I am crestfallen...