Yep

is audacity set to record in stereo on your windows 7?

Update: After getting my sound config fixed on linux it records just fine on linux Still not sure what is going on on windows 7 though, I have to work on windows mainly

Alright so it's not doing the panning on those and also for some reason it's doing the same thing that's happening when the gameboy is recorded, sounding distorted and messed up. Is there some setting I should set on audacity first on windows to record properly? I'm not sure what's going on. I was thinking maybe my sound card is going out on the laptop, but the audio jack works fine and I still get sound on the laptop's onboard speakers...

Do a quick test with one of your Korg trackers and try some hard panning. Then you can rule out an issue with the cable and mic in doing some conversion to mono when you dont want it to. You might just have an issue with your gameboy jack or some failing component inside. If you added a line out on your gameboy you could at least bypass the stock jack.

You're probably better off using a USB audio interface instead of the built in jack to record. Even a basic one like this should give you much better quality:

If you do buy that one, you'd also need an RCA adapter.

I've had this problem when trying to run my smartphone through to my car's RCA input jacks. With some cords it sums to mono and makes it sound all screwy. With others it works just fine and all the sound comes through. So odd.

The cable tip that goes into that jack has 2 black rings on it.

how many rings are there on the jack your using? 1=mono, 2=stereo.4

Wouldn't be the first time It's the usual laptop mic jack has one port headphone jack has its own port.

I think windows is full of shit. Or its some weird non standard 3 pin mic/headphone combo jack?

Well on windows it says it has a stereo mix in recording.

sounds like its summing to mono to me. Are you sure your soundcard is a stereo input?

Here's an uploaded sample file snippet https://db.tt/VbsaqtPN . Cable isn't picking up stereo differentiations and I don't have a power adapter for the gameboy. It starts off normal and then it does a sweeping effect thing that I didn't add from the gameboy at all, nor want.

A quick way to check if cable isnt stereo or you arent recording in stereo. Do you have panning in your tracks. If so, when you pan right or left, is it playing back in just the right or left ear or is it now in the center?

The hissing is normal and part of the charm as zii.hrs said. Once you record you can use a gate and filter it out. A dedicated line out on the gameboy would improve the quality of the audio. Your headphone jack might also be dirty and or having issues.

As for the phase sweeping you are getting when recording. Are you plugging a power adapter into the gameboy when you are recording?