RF Feedback at 10 W locks TX in Tune Position Requiring Tap of the Keyboard Space Bar to Clear

This evening after rearranging my Flex6500, AL811H, and PALSTAR HF Auto, I experienced the unique condition of RF Feedback (I think) that would not let me unkey from the TUNE position with my mouse.  I discovered I could hit the space bar on my keyboard and that would return it to receive.   It does NOT do this when I transmit using PTT or key the MOX with the mouse-only when I key the TUNE button with the mouse.  I have toroids on about every lead in and out and I have ground jumpers from each piece of equipment, but I do not have a ground system in my shack to carry them too.  It performs just fine into the dummy load.  My antenna is a random length long wire that is feed by coax to a good rf choke, 50 feet of LMR400, another good RF Commode mode choke, a 9:1 balun (at which point I have a ground system of radials, and then 117 feet of wire.

My question is has anyone else experienced the odd behavior with the keyboard and any suggestions on where the RF is getting in and to specifically what is it messing with?  At 4 watts out, no problems, but at 8 watts out-RFI is present.   Again this only happens using the tune button.    Thanks, Andy NU5O