One sick Yaesu FT-1000MP . . .

I have a sick FT-1000MP. Last night there was suddenly no TX or RX on 160m or 80m in either SSB or CW. All the other bands were fine. Then I was listening to Argentina on 40m and suddenly that band disappeared too. The receive just dropped away and I had no TX either. I turned on the rig first thing this morning and everything was fine. I had TX and RX on 160m and 80m and 40m. But after about only three minutes, 160m and 80m were gone again.

If anyone can help me diagnose what's wrong with the radio, I'd be greatly appreciative.

UPDATE: I can hear 40m on Sub VFO-B but cannot TX on it. Same with 80m. Same with 160m. However, I can only RX on these bands when I have the same band selected on BOTH VFO A and VFO B!! If I select, for instance, 40m on VFO A and 80m on VFO B, nothing. But if I select 40m and 40m on A and B I can hear audio no problem. Hmmmm . . .