Here is a list of my gear.

Ibanez AF95 Semi Hollow
Fender Squire Tele
Line 6 PodXT
Focal Spirit Pro Headphones
Denon AHD600 Headphones

I am having a lot of hiss and noise when I plug my guitar's into my PodXT's 1/4" input. More so on the Fender (which I just bought used today) than on my Ibanez but none the less present on both. I am listening on my headphones and the problem is there with either pair. The 1/4" cable from guitar to PodXT is brand new.

When I touch the PodXT or the guitar strings or the headphone jack (basically anything metal) the hiss/noise is reduced significantly. How can I get around this issue? I do not have an amp to test without the PodXT in the equation. I bought the PodXT off eBay a week ago and hadn't much used it until today with the Tele.

What can I do to narrow down my problem? Why would the noise be more apparent on the Tele than the Ibanez?

Tele is single coil and on top of that the metal plate on the bridge pickup acts as an extra antenna. Single coils are super noisy when on distortion settings, it is just the nature of the beast. There are some mods where you can layer your pickup cavity with special foil (look up Stewmac, Carvin.com) to minimize noise, other people pot their pickups to lower the noise. You could also look into humbuckers or single coil sized humbuckers, I think Seymour Duncan has one or two models (Hot Rails?).
You could look into the POD manual and see if you can dial in a noise gate on your patches, that should also lower the noise somewhat.
It's 100% normal that some noise goes away when you touch any grounded part in the signal chain. The only fix would be using active pickups which do not suffer from this problem. As diabolical suggested, you should screen your pickup and electronic cavities using copper tape. There's a ton of info on how to do it.

Edit: if you, or your neighbours use those cheap light dimmers, you will hear them. That crap produces an absolute ton of noise!
Last edited by ArturPr at Aug 26, 2016,
ArturPr you are correct about the dimmer.

Before I read the responses I was getting pissed off. I went to Best Buy to buy an amp (to return after experimenting, sorry Best Buy) and some new cables. Had the problems persist. The Pod does not have a ground prong on its power cord. I took a piece of wire and attached it to the ground screw behind the receptacle plate and notch the plate. (Hidden behind my piano as the pod sits on piano) and ran the new ground wire up the cord with the power taping it in increments. I touch the new ground to chassis of the pod and the noise is cut in half. It is likely tolerable. When I touch the strings the noise is almost completely gone. If I touch the pod in addition to the new ground path I ran the noise is almost completely gone. Maybe I need to wear a ground strap to the Pod while playing... Yeah right.

Anyways, I turned off my LED pot lights above me and the noise went almost away. It was a complete accident I noticed as I still had the headphones on. Adjusting the dimmer alters the noise floor as well. The amp has the same issues. My place is full of LED lights and dimmers. Shit. Lol.
If the Pod doesn`t have an earth pin on it`s power cord, it will be noisy. I suggest modifying it, or giving it to someone with experience, basically you want to connect the earth pin to pod`s signal ground. Simple, but you are working with a dangerous voltage and you probably don`t want to fry your Pod
The Pod doesn't need a ground because it's a PS that isolates the AC power from the DC output. If you touch the strings and the noise lowers, then it's likely the ground wire from the input jack to the bridge on the guitar is not making contact. That and single coils will pick up radiated noise from external sources.
Every power supply isolates AC from DC, and the earth pin isn't really a part of AC, it's a connection to ground (literally)