While I am glad that "something" worked for you, USB suspend/sleep has absolutely nothing to do with Flex ethernet control. It is not a "virtual USB port". WSJT-X controls the Flex radio over ethernet using TCP UDP packets. Nothing else. I have a Flex 6600, and have seen the same exact issue with no TX after long idle periods. Killing and restarting WSJT-X always fixes it. But the WSJT-X code is not doing anything with USB ports in this configuration. The issue does seem tied to the virtual AUDIO ports. I tried your USB suspend setting, and I still get the NO TX issue after long idle times. I am leaning toward thinking there may be some similar timeout issue with Windows 10 audio devices, or a slow memory leak or bug in WSJT-X with regard to this. In all cases, restarting WSJT-X fixes it, so you can't blame the Windows 10 USB layer or the Flex DAX layer. Let's keep hunting....
