The receive on my 6500 is nearly nonexistent when I boot it ir change bands. To get it back I have to switch the ant from ANT 1 to XVTR then back to ANT 1 then it is fine till I change bands again or re boot. However the transmitter always has output.
have you tried a Hard reset? 1st Export your profiles to some where like your desktop. 2nd Do a HARD Reset (look in the 6500 Manual) 3rd After the hard Reset then check to see if it works correctly, boot up frequency should be like 14.100 if I remember right if the hard reset worked. 4th Import your saved Profile, MAKE SURE you have the "Preferences" checked OFF, then import the Profile.
See if it still works If not you may want to do a support ticket.