If you just hear a "pock-pock-pock" noise at both outputs (BALANCED MIC OUT and LINE OUT) of the BluBOX, this is due to an unsuitable power supply unit. Presumably you're using an alternating current power supply (in this case "AC" is written somewhere on the power supply instead of "DC"), or the polarity of the plus and minus is reversed or swapped ("center positive" instead of "center negative"). In both cases, a different power supply should be used!

Here you can find the correct BluBOX power supply specifications‍.