This post applies to both Note 2 and Note 4. The following are bugs I have encountered in both phones so far, I have app version 18.104.22.1683.
when jumping from one track to another, sometimes the next song starts and no audio is heard. this happens when using the headset, bluetooth speakers, and the in-built speaker. workaround is to manually cue the progress bar back to the beginning.
when sharing to other apps, spotify needs to be online. this really is not much of a problem but i sometimes have spotify on offline mode and i have to go to the settings before i can share. it wasn't like this before.
when you start a shuffle play with a playlist, the "repeat all" is not auto-enabled. it used to be auto-enabled.
when you clear the recent apps, spotify continue to play, and it's great for that. however, the lockscreen widget info and cover art is stuck to the last song being played before clearing the recent apps. even after closing the app, the lockscreen widget and cover art stays. it only can be cleared by going to the phone settings and stopping the app manually from there.
Please read the guide linked below for details on the most common issues and how to fix them. Usually a clean install is the first step to take and resolves most of the usual issues; the guide details the steps to take to ensure a full 'clean installation' is achieved - This includes checking redundant folders and a REBOOT!
Thank you for the info, Daniel. I am not ready yet to do clean install as I have several GB of offline music on my phone and it would take me some time to re-download it. I do have one more issue that I failed to include in the list above- volume is amiss on one notch: i.e.: volume level goes from 1-15 and it progresses alright through every level except for 14, which actually goes to the same db level as 12. I followed one of your instructions about uninstalling other apps that may be interfering with the sound management of the device but to no avail. The stock music player and even DJay 2 doesn't have any problem at all with the volume level; and btw I did uninstall DJay 2 but since there was no effect I re-installed it. I'll update this post if these issues get resolved with clean install. Thanks for such an informative post.