Broken ground phono connection

Is a 5vdc ground the same as a 120vac ground?

Not ALL grounds are equal. Really they are not.. AND you don't want them to be either.. A 5 volt dc computer ground is not shared with 120 volt ac ground.. A - doesn't always mean ground, there can be - and + voltage from a neutral position.. The way a joystick works with many variable voltages. Analog remotes.

Any screw will do IF there is a white metal contact. CLEAN the screw and make sure the screw hole is good and clean.. metal to metal..

You can drive  12" nail through it and use jumper cables too.. Oh OH.. That's vampire slaying, with a twist... :-)

Regards

The ground on the chassis is the same ground that the phono ground is attached to. It doesn’t get more simple than that! 

Thanks, again!