I want to build a simple voltage follower to buffer headphones with the OPA1688. It will just be built on protoboard, considering how simple the circuit is I think it should still be possible to achieve close to the advertised ultra low distortion.
I will just follow basic, good design principles that you will find in nearly all op amp datasheets: Tying the output and inverting input pins directly together to keep feedback loop as small as possible. Adding ceramic bypass caps directly to the power pins. Adding individual ground wires from the power supply for audio inputs, audio outputs and bypass caps. I can not test how well it performs or even if the circuit will be stable, but surely following those steps there shouldn't be any problem?