Every time you introduce any new piece of gear, there is a chance that something might be off. Ground loops, house wiring, cable problems, etc. Lots of thing can go wrong that are not the fault of the manufacturer. But, of course, there are also issues with slight variations between parts that at times can add up to problems with the component. Luckily, mine has been put together like a tank - so dead-on consistent and reliable that I feel like it would survive a truck being driven over it. That’s why it’s so heartbreaking for me to sell my Stratos and Tempest - their sound is locked in so well that anyone who has heard it has been surprised by them (including Fritz from Fritz Speakers).
The bulbs that I refer to are the ones inside the amp that light up the Odyssey logo. I think they are LED now, but on older ones they are tiny incandescent bulbs that are somehow important to the design. Some folks who removed them to make their rooms darker, noticed a hum that they eventually cured by putting the bulbs back in. Covering the light from the outside is very easy by cutting a piece of black paper to match the size of the hole.