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I am getting nasty electric shocks from guitar to microphone with my X3 Live. I have a much loved Pod X3 Live - and I have recently discovered (in our new practice room setup) that I get shocks when holding guitar and a properly grounded microphone. I have troubleshooted the system and mains supply thoroughly, and traced this to the way the X3 Live processes incoming phantom power. I have excluded bad grounds on all devices, except the Line 6 POD X3 which has no independent ground via its (original) Line 6 power supply - (ie the ground is 'floating' as it should). The negative power supply connection is not ground. I bought a new digital multi-meter to troubleshoot this. I though it was a mic signal path problem at first but have now ruled that out. I've measured 48-50V between the guitar and any good ground, eg the vocal mike in our studio /rehearsal setup - and other guitars, rack kit chassis etc. Though just 50V, it's still a noticeable shock, a lip on the microphone was the first experience and is quite a 'belt' very much felt with fingers too. The voltage drops to zero when I turn off the (global) phantom power on mixer My signal path is: Guitar > Pod X3 > XLR out L to Desk (for monitoring) and XLR out R straigh into to a Firewire 8/8 Recording interface. If I have phantom on on either of those, there is 48-50V potential between the guitar ground and a microphone. Turn both off, no voltage present. The conclusion I have come to is that there is a problem in the Line 6 Pod X3 Live unit that's causing the phantom potential to raise the guitar input's ground wire to become 50V above ground 'proper'. As our desk is Phantom Power 'global' (and other devices like active DI boxes and condensers need the phantom), it's not something I can turn off except perhaps by buying a decoupling transformer as a phantom blocker. I've tested adding a ground wire from my guitar to another guitar (other ground) - to check that the mixer phantom power supply does not object to that by just sending the unwanted 50V to ground - and remaining phantom-powered items connected to the board are still operating OK. They do. So I'm thinking to jury-rig a 'proper' ground to the Pod X3 Live unit somehow to defeat this issue. I'm minded to make a cable that connects one end to a good ground- the mains socket - and then using only the green earth wire of course, and connect this ground to the X3 Live to an used connection (XLR Microphone input Pin 1 ) which my meter tells me is on the same ground buss as the guitar input (as it should be). I am well out of warranty with Line 6 on this unit, while Line 6 have been very helpful to me with an issue I had once before (on my Variax 300) - I'm not expecting their help on this or for this to become a 'send back for repair issue', and am not sure if it's a problem that has always been present and I have just noticed it... My question to the forum community is: has anyone else experienced anything like this? Perhaps in the X3 schematics there is something that shows the circuit schematic of how phantom power coming into the X3 Live through the Direct Outs as is in my case, on pins 2&3 is raising the ground voltage of the guitar input to 50V above 'good' ground. Perhaps there is an internal component that has failed. If so, what would it be? Is there an internal decouplng transformer to disregard any incoming phantom voltage that has failed? Thanks for your time reading this.