7th gen iPod Nano bad flutter on podcasts

My 7th gen iPod Nano periodically suffers bad flutter on playback of podcasts, with the voices and music sounding rough and choppy, in the same manner as on a really bad turntable back in the days of LPs. When it happens, I perform a reset, reload everything, and it'll be alright for a week or three until the problem happens again. I'm getting a bit tired of having to perform resets and reloads. Any suggestions on how to avoid the problem?

I also have an older iPod classic, and I have never experienced the same problem on it, though I also put the same podcasts on it through the same copy of iTunes, so the problem would appear to be the iPod Nano itself.