What should I do about ungrounded outlets in my rental?

Using a really long extension cord might not be the best idea. You could run into ground loop issues, which can create electrical noise and even shock risks. In music setups, this kind of situation can lead to getting shocked just by touching a closely plugged device. If you can, see if an electrician can give you advice on your setup.

For your own safety, you really shouldn't run any metal-bodied appliances from ungrounded plugs. It's just too risky, especially with devices that could give you a shock.

Years ago, I had ungrounded plugs and ended up with some fried electronics after a close lightning strike. I ended up grounding my connections myself using heavy gauge copper wire and grounded plugs. Now everything works fine and no more issues with fried devices! Just something to consider if you're worried about safety.

Honestly, I'm surprised that the lack of GFCIs in rentals like this isn't against code. You should definitely check that out. I mean, you could push your landlord on it, but be ready for the possibility of needing to find another place if he isn't responsive. You'll probably have better luck in a place that has proper grounding!

Honestly, that place has been fine since 1963 without grounding! As long as your power demands aren't through the roof, like running a full mining farm, you should be okay. Just keep an eye on things and be cautious!