Hot answers tagged accompaniment
Skype should work, or perhaps zoom https://www.zoom.us/. Your problems have nothing to do with VoIP (if you can tolerate the latency) but with the playback setup in PA. Get a decent sound card, a decent headset and perhaps a headphone pre-amp. If the acoustic piano is really that loud, try a noise cancelling headphone.
It looks like there's a software called OhmStudio that might meet your requirements, at http://www.ohmstudio.com/ . However, as others have pointed out, latency can be a real issue here. Data won't transfer over the internet instantaneously, so there might be some latency - you both likely won't be able to hear each other in real time. As per my above ...
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