Balanced RCA cable

I've found a video on YouTube that mentions a term 'balanced RCA interconnect'. It's described as a cable with two independent leads and a shield.

I just finished soldering my interconnects and they just happen to be one of those. I bought them second hand, so they might have originally been balanced (the normal ones), where someone just ditch the connectors in favour of RCAs.

I've wrapped a cable shield around one of the internal leads and soldered altogether as a ground, on both sides. However, this guy on yt proposes that a shield should be connected just on the amplifier end and left floating on the other.
What's the proper way to do it?
 
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I've wrapped a cable shield around one of the internal leads and soldered altogether as a ground, on both sides. However, this guy on yt proposes that a shield should be connected just on the amplifier end and left floating on the other. What's the proper way to do it?
A shield must not carry current, so it has to be connected only at one point.
Usually, connecting the shield to the source chassis works best.
 
RFI is more of a problem with a discontinuous shield. This is why audio inputs should always have RF filtering right at the point of entry into the chassis, typically something like 100pF to 300pF ceramic to ground on the connector itself for a low impedance signal. Audio cable braiding is often leaky at RF anyway (its hard to make an RF-tight shield that's nice and flexible).

Whether interconnect shields should be continuous is a complicated matter - it might be the only grounding route for a remote unit for instance, and then you definitely don't want the remote unit to float, voltage wise. Most indoor environments are riddled with mains fields in the dozens of volts range, so floating can mean a lot of mains hum.
 
This doesn't make much sense. If an audio signal is essentially a voltage difference between a signal lead and ground, why would we just cut one of them?

Are all grounds the same? If that is so, I recon that all electronics manufacturers would just use a signal wire from interconnects and a random ground from that device's chassis. Then we wouldn't have the ground loop problem in the first place.
It can't be just to shield from RFI a bit more.