Good contact is necessary only between earth tag and chassis for safety reasons.
If one experiences audio problems that are due to incorrect contact between Pin1 and chassis, that's because there is something wrong elsewhere. The cable shield is intended for electrostatic interference protection. It should not be relied upon to ensure galvanic continuity between equipments. No current should flow through, so even a very poor contact should be perfectly adequate.
If one experiences audio problems that are due to incorrect contact between Pin1 and chassis, that's because there is something wrong elsewhere. The cable shield is intended for electrostatic interference protection. It should not be relied upon to ensure galvanic continuity between equipments. No current should flow through, so even a very poor contact should be perfectly adequate.