When we go to post and item it displays a blank page. When you click refresh it repost the items. Any suggestions?

A white page means there is a PHP error.
Please enable error reporting from the Global Configuration menu (server tab) to see the actual error.

Notice: Undefined property: TableK2Item::$category in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 293 Notice: Trying to get property of non-object in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 293 Notice: Use of undefined constant jsk2 - assumed 'jsk2' in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 308 Notice: Use of undefined constant comment - assumed 'comment' in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 308 Notice: Use of undefined constant jsk2 - assumed 'jsk2' in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 310 Notice: Use of undefined constant like - assumed 'like' in /var/www/clients/client10/web41/web/plugins/k2/jsk2/jsk2.php on line 310 Strict Standards: Only variables should be assigned by reference in /var/www/clients/client10/web41/web/plugins/k2/broadcastk2/broadcastk2.php on line 34 Fatal error: Class 'JParameter' not found in /var/www/clients/client10/web41/web/plugins/k2/broadcastk2/broadcastk2.php on line 35

These errors are from 3rd party K2 plugins.

/broadcastk2 and jsk2 (?)