Spinner and box lock problem

Hi all , I have a VU+Ultimo 4K with Openvix 5.4.013 installed. My problem is I keep getting the spinner coming up randomly in the top left corner of my screen. I can be in the middle of watching a tv program and the spinner will appear for 10 seconds or so every so often. Also this tends to happen a lot when I am browsing through the epg, the spinner will appear and the box becomes unresponsive for say 20 seconds at a time and then again after a short period of time and so on. I thought it may be the epg cache full so I deleted that and tried switching between hdd and internal flash for epg location but it’s still the same after deleting. Anybody have any idea what may be causing this?
Thanks