Very slow GUI on a Pi 3

I’m using a Raspberry Pi 3 running Volumio 2.041 with a DigiBerry. I created a new install of Volumio to try and solve my NAS related library issues (nas-library-mounts-but-won-scan-t6007.html), and this worked but now the GUI is incredibly unresponsive at times.

I usually get a spinning rectangle or the spinning dots while the fonts are all messed up. Even after several minutes I can’t click through to my library and accessing each section of the app takes a long time. This is essentially the same whether I’m accessing it through my Mac, my Windows 10 HTPC, my Android tablet or my iPhone 6.

I can SSH to the pi without any trouble and entering the “top” command doesn’t show any processes taking up particularly significant resources.

Are there any terminal commands I can use to clear a cache or relaunch the GUI to improve performances when this happens? Or am I barking up the wrong tree here? Is it more likely to be network related? How can I go about diagnosing what’s causing this?

Many thanks for your help, as always.

Maybe this is the same issue?

To me it sounds like a networking problem. Are you on wifi? If yes, try to use ethernet

Unfortunately it’s in a different room to the router so wifi is all I can do. I didn’t have this problem before switching to a Synology NAS from a WD one, so I suppose I should be looking for faults there. Got to say I’m really unimpressed with the Synology compared to the supposedly inferior WD My Cloud, been nothing but trouble so far.