Samba crashes while transferring files

I’ve got CoreElec running on an Odroid C4, with an external USB hard drive. Playing from the drive works great. However, reading and writing to the HD from the network has issues. If I use a Fire Stick to play files on the shared HD, it will sometimes stutter and freeze despite a good network connection. If I’m copying a few GB of files to the HD, it sometimes works fine, sometimes slows down to 50% speed or worse, and sometimes stops responding completely. When that happens, disabling and re-enabling Samba fixes things. Any thing I can do to get Samba to be more reliable? Lock it to SMB1? Or SMB3?