I'm not sure why the sound wasn't working for you as I tried it over two devices and I can hear it on both, what OS are you using?
I was actually considering adding cash per tape and allowing up to 2 more VCRs to be purchased in the 2 spots below with a simple click.
In regards to the swapping a rewound for unwound tape, I did consider whether to provide that information straight away or leave it to be discovered, so you'd prefer to know that off the bat rather than an 'easter egg' of sorts?
With the telegraphing when a tape is finished, do you mean some kind of countdown bar etc? at the moment its set to rewind over 5 seconds and has sound attached so you can hear when its done when out of view but that isn't helpful to you if sound isn't working haha