ESP32-WROVER is fundamentally broken (but is being fixed by Espressif now)

We are still experiencing different issues with the ESP32 on the Pycom devices, see also

Thomas Rogg of Neonius seems to have found a glitch related to PSRAM and dual core mode.

While we are not into the details of this yet, you might enjoy diving into it. It looks like Espressif is working on a workaround solution shipped through ESP-IDF to mitigate the issues for all the silicon which is already out there.