Thanks, that's definitely a similar issue. Interesting that I can compile under debug and not have the issue at all. The w5500 works perfectly and brings the link back up even with multiple cable unplugs. Hopefully they can look at this bug soon. Thanks again!

Using IDF 4.3-dev with the debug compiler option from the menu I have a working example using an SPI-connected W5500 ethernet module wired to the default pins for SPI3 - the example starts up, configures the mac and phy and gets an IP address but only if I use an SPI bus speed of 32MHz. I can then s...