Ok, this isn't a tough one at all. There are 9 peanut bulbs (I think they're the same part number as the bulbs for illuminating your dummy lights in the cluster). One behind each button.
The fact that the bottom row is intermittent rules out a burnt bulb. You have an intermittent connection. Pull the assembly out of the car completely. Inspect the pins on both ends of each connector. Are any bent or corroded?
If pulling them apart and re-seating them doesn't do the trick, disassemble the switch pod from the console fascia. You may need more than two hands to do this. There are plastic release tabs underneath the assembly on the sides facing the driver and passenger. after disassembly, remove the 3 bulbs on the rear row, and clean the contacts on the bulbs and sockets. If something was spilled on your console, it could cause this.
I'm betting simply disassembling it and re-assembling will solve the problem. It should take no more than 30 minutes, and no tools (other than something to release the tabs) to do this.