Podcast app changes playback speeds by itself

Sometimes—not always—the standard Apple Podcast app changes playback speeds while I’m listening to it. It suddenly increases to 1.5x, then 2x, and cycles continuously through the speed options. Sometimes it stays on 1.5x for a while, and I can cycle through manually to get back to 1x. I’ve tried closing the app and reopening, turning the phone off and back on again, deleting the app and reinstalling, but the problem always comes back sooner or later.

I rarely listen to Podcasts anywhere other than in the car. Could it be vibrations causing the speed to change? At any rate, it’s very distracting to have to change playback speeds every minute or two while driving.