CS4397 dac

[FireFly]

Some news:
Capacitors C32 and C33 (original value 56pF) should go out. Op-amp will not oscillate without them , they are killing highs.
Capacitors C34 and C35 (original value 1nF) should go out. Or minimal value of 100-150pF, as Leo suggested.
C44 and C51: desolder original 100μF, put 47μF.
C40 and C50: leave original SMD, bypass with 0.1μF MKP (small size)

Bottom side of the board:
Solder lytic capacitor 4.7μF or 10μF directly to op-amp legs 4 and 8 (4=negative, 8=positive) for decoupling. Use good quality cap.