The Danish version is “Tomme tønder buldrer mest”.
From Shapespearre : (Henry 4., 4,44, fra 1598), 'This saying is true: ‘The empty vessel makes the greatest sound’.
An older variant is Danish in Anders Sørensen Vedels Saxo-translation 79; 1555, fra/from år/year 1575: ‘Tomme og usmurte vogne buldre altid mest’. (“Empty and ungreased wagons makes the loudest noise” , freely translated, ‘Bulder’ is the sound you get from knocking on an empty barrel). Saxo Grammaticus wrote “Gesta Danorum”, an extremely unrealiable history of Denmark and the Danes.