I have a LimeSDR-USB (v1.4s) that has suddenly stopped working. It is no longer recognised as a USB device when connected to a computer. (E.g. on Windows I no longer get the sound indicating a new USB device has been connected when plugged in - and there is no new device displayed is device manager). Have tried on multiple computers with the same result. Have also tried hub and direct USB 3 ports.
When connected, all four LEDs are solid (2 green, 2 red). I tried disconnecting the FX3 jumper - no difference. Neither does pressing it’s reset button.
Probing the USB differential data pins shows them as both being low. Probing the FX3’s 19.2MHz crystal XT1 also seems to show no activity. Neither does there appear to be any activity on the clock line to its SPI flash. The FX3 seems to have some power, as it’s getting warm.