Here's something new - a friend of mine and I were at Macy's today (we rarely go) and happened to buy some things…Discover via Apple Pay worked fine for her, but for my turn, my Visa card (credit) caused the register to shut down and reboot twice (card terminal was "processing" and lost the connection to the register once it rebooted). The register looked like it was running Windows 8+ and eventually worked with the same card as a chip. I'm not sure if anyone has seen anything like this before, but I haven't in the 2+ years with Apple Pay…
Macy's contactless processing is a bit odd, so I can't say I'm too surprised.