In the case of the Audiolab 8300A, it wouldn't matter much as it clearly sports a 2-prong mains connector and as such must have a floating audio ground.
A lot of other gear with balanced inputs has its circuit ground tied to protective earth, however, including most things studio / pro audio. It only takes a PC and some common active monitors (JBL 3xx, KRK Rokit etc.) for ground loop issues to arise when (effectively) unbalanced connections are used between them - nothing complex or exotic at all.
