SanDisk Sport Plus shuts down after playing a few songs

I have had this for about a year, and have great difficulty with the following:

1.  It is difficult to keep my earphones connected to MP3 player.  Disconnects (left ear) or pulses on and off.  Player is less than a foot from these JBL wireless Free ear buds.  Battery is fully charged.  Ideas?

2.  Player shuts down after playing a few songs requiring a system reset etc.  Battery is fully charged.  Very annoying.

Any ideas?  I have the up-to-date firmware etc.

Thanks much!