Line fault at the outlet -- do I need an electrician?


Yesterday, I got a Panamax, Max 1500 surge protector and line conditioner. (I got a very good deal on it, and am just trying it out.)

I plugged it into an outlet I've been using for a while and one of the red lights on the front lit up saying "line fault." (I'm not sure how this is different from a "ground fault." Maybe it's the same.) The Panamax does not do this with other outlets in the room. They seem ok.

So, I know this means that the outlet is improperly wired. My question is, might this be a simple thing to check and/or fix? Any suggestions most appreciated. It's the only outlet I can use to have my audio set up where I usually have it. Now is not an optimal time to call an electrician. If this is a big problem, I'll try out my gear somewhere else in the room, but if I can fix this without too much expertise, that would be ideal.
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Ok, here are some results.

TESTS for two connected outlets:
Ground contact of wall outlet TO Hot contact slot = 4 volt reading
Ground contact of wall outlet TO Neutral contact slot = 120 volt reading

TEST for another outlet on a different circuit in same basement:

Ground contact of wall outlet TO Hot contact slot = 124 volt reading
Ground contact of wall outlet TO Neutral contact slot = 0 volt reading

I suppose this means I have reversed polarity on those problematic outlets?
I don't know why I got a 4 volt reading in from those outlets.

Hopefully you fix the last receptacle in the circuit, otherwise you'll have to change out the rest because they'll now be reversed. 
Well, it seems you've done it. Congrats.
Oh, I misread. You just need to reverse one, then the next one in line will be fixed.
@cissado -- I would need to reverse the initial one, no? Or perhaps it's messed up all the way back at the box? I am shying away...