Audio Problems with Sony CDX-656 Changer and VW Gamma HU

Hi all,

I've just added a Sony CDX-656 10 pack CD auto-changer to a UK spec.
Passat using a Connects2 VW - Sony adaptor. The HU is an older Phillips
Gamma 4 (Gamma under volume control). Adaptor is AVGS005. All works fine,
but I can only get it to work correctly with both phono connections half
out (center pin only connecting).

If I push both phono connectors fully into the Connect2 adaptor then the
audio cuts out on one channel (normally left), the other channel is fine.
If I push both phonos half in so the center audio pin is connecting only,
and the outer ground ring not touching then I get audio from both channels
fine but I'm not making a sound connection (since the phono is not pushed
fully home) and audio is intermittant as the adaptor jiggles around.

The adaptor is a small metal box, and required a 12V connection, although
this is also used to feed the changer power. The CD changer body is is
plastic (I beleive). No evidence of a ground tag (for a grounding lead)
on it or the adaptor housing.

The changer is mounted in the boot, horizontally under the parcel shelf if
it helps. I didn't mount the changer, or run the cable, simply fitted the
adaptor to the HU and hooked up the power. Both the changer and adaptor
are new.

So, any idea whats going on here and how I can diagnose and fix it? Im
okay with electronics, just a newbie at car audio installs!

Cheers,

~Andy

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