Quote Originally Posted by Shea08 View Post
I have ... also changed the download location in expert settings to /mnt/sdcard
That DEFINITELY won't work. Android won't let BeyondPod write to your SD card there.

HOW have you tried to move the podcasts to the SD card? Here's the help page: How to change the location of downloaded podcasts

See also the information at My External SD card has become Read Only and Troubleshooting External SD Card issues

Your podcasts MUST be in BeyondPod's private folder, which will be ~/Android/data/mobi.beyondpod/files on your SD card. On Marshmallow, I would expect the path to the SD card to include a unique identifying number for the card. The exact path that Samsung uses may be different, but on my Sony, it's /storage/nnnn-nnnn/Android/data/mobi.beyondpod/files, but you'll sometimes see that presented as a symbolic link, e.g. /storage/emulated/0/Android/data/mobi.beyondpod/files