Approximately last few months I am experiencing problems with OpenLayers plugin in QGIS - especially with OpenStreetMap data.
The layer loads sometimes terribly slowly although the connection is quick enough. Sometimes during map panning I get damaged colors or black background.
I had similar issues both at work (latest 2.18 LTR, 64bit Windows 7) and at home (latest 2.18 LTR, 64bit Kubuntu linux).
Is there any issue in OpenLayers plugin or it is just caused by increased traffic on OSM servers which are temporarily overloaded?