Vintage 1970's El Degas Lawsuit Era EB-3 Bass Copy - Japan?

This listing is for a vintage 1970's El Degas brand EB-3 bass copy. It isn't marked, but I'm pretty sure it was made in Japan based on the general construction and the 'open book' Gibson style head. I would say it is comparable in quality to an Aria, Univox, or early Ibanez of that era, and was probably made in same factory as some of those. The bass is finished in a reddish brown like the early 70's Gibsons you see, and it features a bolt on neck and two pickups with rotary selector switch. The covered bridge even has a flip up rubber mute feature. The scale length is 30 inches and the neck has a fairly narrow profile which makes it great for the guitar player who occasionally needs a bass. As you can see it's picked up some finish chips, dings and scuffs over the years but there are no breaks or repairs. One tuner bushing is missing. Both pickups work and have a wide range of tones, but for some reason all of the knobs seem to function as tone type controls and none of them raise or lower the volume. The wiring appears to be all original (see photo), so I assume there is simple connection or solder issue. I'll leave the wiring repair up to the next owner, but again it's playable and sounds great as it is, you just can't turn the volume down on either pickup. I'll include a non-original gig bag. I'm including plenty of flash and non-flash photos so take a good look to see the condition, etc.