I've learned a lot in the last 24 hours and it wasn't all fun or easy.
The Microphone Problem
I still have a support ticket open with Flex for my new radio's front microphone connector, but today I got the go ahead to open the case and inspect the ribbon cable connection from the circuit board to to the front panel.
WHAT DO YOU KNOW IT WAS DISCONNECTED!!!
So I re-connected it, put the radio back together and BAM, my Heil mic and hand switch are working. Dudley the Flex tech support guy is great to deal with.
The Crash Problem
Last night was tough. After a couple of evenings playing around on 80m and 40m I finally had band conditions suitable for playing around on 20m as well. So on 20m I keyed the mic and the PowerSDR software froze and died! I rebooted everything and tried again, same result. I rebooted and went back to 80m and 40m, no problems. I then went back to 20m and keyed the mic once again, and CRASH.
This pattern of crashes and reboots went on for a few hours of troubleshooting and I finally went to bed frustrated. As I sat watching TV I composed an email to the Flex owners mailing list and for the next 24 hours I got some great replies from people with solid advice and things to try.
#1 - Better Firewire Cable - So today I started by ordering a new 6 foot firewire cable from Granite Digital. This premium cable was highly recommended by multiple responders to my email. CHECK!
#2 - Better Grounding - Second I built some insanely big shielded grounding cables. One will go from my ground system to the back of the Flex (replacing the one I was using). And the second will go from the back of the Flex to the back of my PC. As multiple people reminded me an SDR is one radio made up of two components (the 5000a and the PC). I went to a car audio shop for the great flex cable and suitable connectors and I borrowed the solder pots at work to dip the ends for a nice fit and finish. Do you think I over did it? CHECK!
#3 - Shield from RF - The unanimous advice from all the hams who responded to my email was clean up the RF. So with the help of a dozen snap-on ferrite's I put them everywhere. Both ends of the firewire cable (2 per end), the PC power cord, both monitor cables, the PC audio cable, etc. I also looked at all the cables running around and tried to clean up their paths and eliminated anything not required. CHECK!
#4 - Check DPC Latency - DPC is apparently important in SDR and checking the systems DPC score is a way of knowing if your systems passes or fails. I downloaded an app called DPClat and my QuadCore passed well under the recommended level of 350 or lower (my score average between 175 - 200). CHECK!
So with all that extra work I crossed my fingers and plugged everything back in. Powered up the Flex and the PC, and loaded PowerSDR.
I don't want to jinx it, but two hours have gone by and no crashes. I tested on multiple bands with the drive on the radio set to full 100 and everything is working GREAT!