Sound Drops out in Premiere playback

Hi, could someone please help? I'm editing 4k and 5k video from a Vuze XR camera using a Predator Helios 300, PH315-52. The sound plays for about two seconds on a clip, then drops out. If I restart play, it'll play sound for two second again and the cut out again.

Sorry for the newbie question, but I really appreciate the help. The video clips are saved on an external harddrive. Thanks for any advice!