AD8620 decoupling and LF bias

[s23chang]

Hi all,
I've just swap out the op-amp on my Marantz CD67SE with AD8620. I've choosen this one because it's a dual and I figured it's plug-n-play.
After the swap, it sounded a little flat. By default, the old JRC2114 had 100uf decoupling on the circuit board. No high and low frequency extension. I then added .22uf between V+ and V-. This time it improved both highs and low frequency by a lot. It's really nice sounding but the high frequency is slightly forward than what I like.
Since it's my first op-amp swap, I'm not too familiar with it.
Does it require burn-in time to tone down the high frqeuency?

If I change to different de-coupling between V+ and V-, is that going to help? I put the .22uf because that's what I have on hand.

The analog device pdf manual mentioned that we can add a 50K resistor between pin 1 and ping 5 for AD8610. How do I apply this to AD8620? Which PINs should I add the resistors? Has anyone tried this?

Any inputs are welcome!

TIA!

Sam