Silver and copper are the most conductive metals you can get. Your last banana plugs were probably brass with very thin gold over them. Brass is about 70% less conductive than copper, gold is 30% less conductive. Which is horrible for an electrical signal. Which is in all the tests I’ve done tend to dull and smear the sound and restrict the signal, and restrict the soundstage. The ones you upgraded to are far far better conductors and pass the signal less intrusively. And what you are hearing is more of the actual signal and sound of your system getting through. Unfortunately you may be hearing mismatches and warts now as it’s more revealing. You probably based your other component matching on what the other bananas sounded like.
I would honestly suggest not going back. I think you should start with the best and move from there. In the end you’ll be rewarded. However I guess that means you have to find other components or change something out. If you’re not willing do do that then I guess you’ll have to go back to the other ones. But keep the new ones for when you do some day buy new gear so you can add it in then if you do any future upgrades.
I changed out all the brass in all my speaker binding posts, changed it out on my amps, and all the RCA inputs. And got rid of it all in my speaker wire ends, and RCA wire ends and use all pure copper now in everything. The sound difference was immense. Absolutely incredible jaw dropping improvement. However it will reveal any flaws or mismatches if you have any and will be very revealing. Mine only got better and never worse with the gear I have. You may just have one piece that isn’t working with the rest of the system now. The challenge will be now to find out which one it is. If you’re up to it. If not, go back to the old worse, bananas and call it a day for now.