I found out that the blue chip is most likely an Operational Amplifier AD 8656 or AD 8655, I will order the parts and take a gamble to solder it on.

I purchased my trusty iBasso D5 Hj DAC and headphone amp when I lived in Japan a couple of years back. I used it on daily basis with my laptop or PC as a DAC and headphone amp. I had to previously repair the USB at the back, which was simple enough job, but now I think something more complex...