Like every HFI-780 I had mayor problems with the pleather pads.
My pads had cracks in the pleather after 2months , so I asked Ultrasone and they helped me out with 2 new pairs of earpads.
But 1 year later ,they have cracks aswell.
I bought a pair of DT250 Velour Pads...
And those pads are the worst ! They are too big, too soft ,not super comfy, they get dirty when you're using your HFI-780 as a portable and sound is real bad.
The Bass-punch is gone, the mids aren't in balance anymore, the highs are forward ,the soundstage lost the S-Logic effect and direct and forward soundstage got lost.
It just sounds like a strange version of a ultrasone-sennheiser mix.
I kept searching and I found the perfect pads !
The Pads of the MDR-V6 are made of leather. They are just a little bit too small ,but they sound awsome and they are the most comfy pads you can possibly get.
The Bass is tighter than before ,the mids keep their balance ,only the highs are a bit more forward than before. The isolation is close to the original pads.
Next thing I would try is to put some felt behind the MDR-V6 pads to improve the bass-punch,to get closer to the original pad-sounding.
PS: The MDR-V6 pads don't get sold as a pair ,so you've to order 2 single pads. I bought them at thomann.de for 37€