Oldphart syndrome. With this June Gloom I groaned upright and glowed dimly at 0930. Felix came and lifted the 31 XT onto the scale: it has lost 1.3 grams of weight in 20 months. Checked the scale with NIST 1.000 Kg weight. No variance. Hardest part was cleaning the battery. Even dust would add up. But I did slump float voltage with use of monster Shottkey rectifiers to 13.4 for summer. Power has failed several times. I don't know it 'till I see the blinking microwave. BiPAP heaven. The spic and span clean aspect is indeed a joy. About $230,000 to replace the 2-volt cells though :(