I have an issue at the moment on most of my guitars where it will make a very loud buzzing noise (which is made much louder with amp distortion) and it only stops when I twist and fiddle with the cable in the input jack of my guitar.
It has been a minor annoyance but on my BC Rich Warlock it has become majorly pissing me off taking several minutes to get the guitar to stop buzzing, and when I move an inch off my seat it'll go buzzing off again, if I hold the cable into the input jack by hand it stops and when i let go its BUZZZlightyeartotherescue.
It made tuning my guitar really hard, I had to use the stupid tuner in my vyper just so I could get a signal and that took like 10 minutes just to get it right.
I use a relatively shitty Ashton brand cable,
how should I deal with this, better cable or messing around with the guitar itself
Well, since you said it was with most guitars and it's highly unlikely they all broke in the same way, it must be the cable.

The way you described it, it would appear as though inside the cables plug there is a bad connection. Does it make a difference if you turn the cable around?

You could I guess put on a new plug (if you're handy), or get a new and better cable.

Then again maybe it's a message from above telling you this would be a good time to learn to tune by ear :d
Ashton leads crap out after a while. Get a new lead.
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The Ashton lead's I'm using are BRAND NEW by the way, the only reason I use them is because they're the cheapest in the shop and I'll deffs get something more expensive now from a more reputable brand.

Like it makes a difference when I turn the cable around but the window whereit actually works is very small and fiddly, and when move the slightest off my seat it'll buzz again.

And I can tune by ear but I prefer to have it absolutely scientifically perfect (concert pitch) which I know no-one's ears on this planet can deal with.
Its the cable. Either someone twisted the plug around and broke the solder or someone pulled on it too hard and it came loose.
there are a bunch of possibilities for guitar buzz.
1. you may have corrosion inside you input jack.
fix- Use a small piece of 60 grit sand paper rolled up like a cigarette to shove into the jack itself. once you got it in there, grind it about. when you think you've got it good and clean, use a q-tip to remove any remains.
2. grounding issues with amp or ect.
fix- make sure your guitar amp and all your power supplies have a third {grounding} prong. then use a Ground Fault Outlet Receptacle Tester to make sure the wall jack your plugged into has a proper ground.
3.guitar grounding issues.
fix-make sure everything in your guitar is soldered properly with no cold solder joints, and has proper shielding.
while it is true that using a cheap poorly shielded chord can sound like grounding issues {buzz}, the only way to find the problem is to start down the line eliminating any problems as you find them.

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