This isn't a nuclear reactor guys, geesh.

From my point of view once the device was electrically modified your taking chances of electrical faults ANYWAY !!!

I don't believe even Gary is qualified to say if it would still pass as "double insulated" and safe to run as it was (ungrounded) or not. Only a testing lab could say that.

I'm not saying to leave it ungrounded I'm saying to try it, to confirm if that is the problem FIRST. We may be pointing fingers to the Oppo ground for nothing.

If it does work you could ground the Oppo to the amp for safety reasons only. Or have it demodded. You need more info to proceed further IMHO. Would a demodded Oppo be 100% safe as original? Who knows.

I think suggestion of lifting ground on the AMP is worse because these are higher current units and WAS fully designed to be grounded where the Oppo was not (originally). So of the two I still it's better to go after the Oppo (after confirming it is the problem). Ungrounded Oppo would be the lesser of two evils.

Over grounding as suggested *IS* safe but IMHO band-aide-ish (for an audio purist point of view) and often does not eliminate hum completely but just reduces it. You can try that too if you the think the earth will stop from ungrounding the Oppo.

Markg doesn't understand all the risks and everyone has their own view on this. I'm extremely picky and was an electrician for 3 years before going to college for computer science. I don't blink an eye at opening the fuse panel. If you knew how bad so many electricians are in following rules you'd be a heck of lot more worried than an ungrounded DVD player. I wired my own pool and the inspector said I was one of VERY few people that did it 100% correctly. Neighbor had a licensed electrian do it and it never passed inspection. So I'm well aware of the risks here and would not suggest (trying it) if it was that dangerous. But don't try it while standing in a bath tub.

Lifting the ground for 5 minutes is no riskier than driving to work. You can respectfully disagree with that if you want. It's like not wearing a seat belt to the end of your driveway.

People have been lifting grounds on AMPs for years (ones that have no ground lift switch). The world hasn't ended yet. I've done it and I'm sure many here have done it in the past. Generally if I ever have had to do I dig deeper eventually to find the root cause, fix it then reground it. I have no lifted grounds at the moment and have not for quite some time.

And I'll bet at least one appliance if half the house holds have a missing ground. The world won't end if he tries it. But kiss all your loved ones today just in case.

One more thing. It's all about probabilities. What's the probability you get hit by car going to work to day. What's the probability a dna strand will mutate into cancer. What's the probability of being struck by lightning? What's the probability of getting hurt down hill skiing. What's the probability of not landing safely in a small airplane. What's the probability your feet are grounded and your ungrounded Oppo faults in the power supply and fuses a hot lead to the chassis, while your touching it?

Grounds, Seatbelts, Physicals, Airbags etc. reduce probabilities. I assure you the ungrounded Oppo has pretty low probability of hurting you in the big scheme of things.

Does ungrounding change the propability of hurting you, YES. But both probabilies are lower than things you are exposed to every day. Just stay in bed and you'll be safe. Well their is risks with that too.

And the Oppo will still be grounded even with power cord ground lifted through the 3 shielded RCA Cables to the 568.

- Fiddler (IMHO)

If you think listening to music is fun, try learning an instrument.
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