Playback changing/shuffle toggling when locking my phone??

[zkgillispie]

Plan: Spotify Premium (with Hulu)

Country: United States

Device

Samsung Galaxy S8+

Operating System

Android 8.0.0

My Question or Issue

 So this is kind of a weird one: this issue seems to primarily happen when I'm in Bluetooth mode playing through my car, but has also happened while walking with earbuds in. Generally, I'll put playlists or my library on shuffle. When changing a song, I tend to settle on one I feel like listening to, lock my phone, and put it top-first in my cup holder (don't know why, just a routine). On my old iPhone 6, this wasn't an issue. However, since I've switched to an S8+, sometimes when locking my phone or putting it away, a song will skip to the next song on its own, or shuffle/repeat will toggle on or off, or just other weird behavior. It only seems to happen when I'm locking the phone, and it's not a button like Bixby triggering something (I've tested to make sure). The only possible explanation I can think of is that there are some weird motion controls buried in the S8+ settings I don't know about, but I haven't been able to find any. Can someone explain to me what is happening here? It's starting to get really frustrating.

Also, somewhat related, but for whatever reason my phone has just started toggling Car Mode in Spotify in the past week when I'm in my car. However, I've noticed shuffle disabling itself after listening to a song for a certain amount of time? I don't have exact numbers on this, it's just really strange and I'm not sure what to do about it.