yes, I was refeering to the unity volume setting required on the R09HR and the lack of one on the M10. I did have many occasions with the R09HR where I had to change batteries, more often than I ever thought I would... just seeing 2-3 bands on a summer shed tour.
with the M10 I have had no issues at any level, as long as the auto-level button on the back is taped down
again, just based on my experiences