New battery fixed my problem for the most part. The only times it has lost keyboard & trackpad communication has been a couple of times in the past month when I let the battery die down to nothing, then re-starting the computer with power cable in fixed it both times. No problem if I keep it up over 5% power in the battery and I think the fact the old batter was swollen in the middle and was losing power had something to do with causing this problem more and more often as the batter got older. It would be good if Apple confessed to the cause of this problem and provided sound advice.