Tingling feeling from showerhead??

Ive noticed a slight tingling sensation whenever I touch the showerhead - its very faint but very noticeable the other day when I had a small cut on my finger when it was similar to a static electricity shock!!! :o

Dont notice this on any other tap in the house - all plumbing is copper apart from a small section that was replaced with the plastic stuff due to a small leak.

Any ideas? I have a multimeter - can I set it to high volts and measure the potential between the showerhead and a metal stake in the ground outside perhaps?


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