The plumbing for the upstairs bathtub/shower runs between the first and second floors. We get a drip in the first floor ceiling when using the shower only in the upstairs bath. We first thought it was caused by an after market shower head, replaced it, no improvement. I'm a DIY'er but this one has me baffled. I don't know how to access (or even see) the plumbing between floors or behind the bathtub without a major rip-out. I suspect the leak is between the bath faucet and shower head because it only leaks when the shower is used.