I know this is a bug for JW AllVideos content plugin and not K2 but I'm hoping it will make it to the right place...

 

Lines 80-81 in plugins/content/jw_allvideos.php

 

$debugMode                    = $pluginParams->get('debugMode',0);        if($debugMode==0) error_reporting(0); // Turn off all error reporting

 

Complete disables joomla and PHP specified error reporting unless the plugins param is set.  It would be much better imo to default to the Joomla settings leave error_reporting alone all together.