Please contact adsbsupport@flightaware.com for help. 7.10.2 is the current version and works on previously shipped hardware versions; 7.3.0 is very old and no longer used or supported.
edit: actually, you have H4 hardware which is quite old and I had problems with getting 7.10.2 to boot on my test H4 hardware; I suspected hardware problems but as a precaution we didn’t auto-upgrade H4s to 7.10.2. If 7.10.2 doesn’t work, try the previous version: https://flightaware.com/adsb/flightfeeder/files/flightfeeder-sd-card-7.9.1.img.zip