Outlet is "Open Ground" - Is There Still a Safe Way to Connect to My Audio Gear?

Sorry, the metal faceplate of the amplifier.

My home was built in 1956 and has two wire open ground outlets in much of the house. This is true in my listening space. 

I am a fairly avid follower of posts on AG and realize amps, in general, should be plugged directly into the mains outlet. When I do this, I can actually feel low levels of current on the metal faceplate. Pretty scary.

I have plugged my amp into my Panamax surge protector/power conditioner. The grounding issue was resolved. Hopefully this hasn't impacted the overall sound of the amp. It seems like a decent compromise to not have the scary feeling grounding problem.

I have had to replace several duplex outlets over the years. Definitely two wire open ground. There is an addition on the house, built in the 1980's. Those outlets do have the typical green grounding cable, but the breaker box (since replaced and upgraded) was still from the 1950's and didn't have provisions for actual grounded outlets, anywhere in the house. 

I don't have access to the model number of the Panamax surge protector, but it's a fairly low end model. All I know is when the amp was plugged directly to the mains, it's metal front cover conveyed some minor current flow and when plugged into the Panamax, it was resolved.

I am not in a position to rewire my entire home either DIY or via a paid professional. I also don't own equipment anywhere near true audiophile or reference level cost or performance.