Update. I pulled the batteries, and put them in the meter. They were lithiums. 2 showed 1.72. 1 showed 1.32. 1 showed 1.08. These were fairly new, and there was no "low batt" indication with I fired up the scope initially. This is the 2nd or 3rd time the scope has done this since the "sleep" mode became part of the software. Interestingly, when I put in brand-new batteries last night, and changed sleep mode to 5 minutes, and did not let it go to sleep, it continued to work with no problems.