SharePoint custom field control intermittently reverts back to text field

This is maybe a long shot, but I have a custom field control that renders a colorpicker field for a custom SharePoint list. The field control inherits from the BaseFieldControl.

Most of the time everything works fine, but every now and then the control will revert back to a normal text field within the list. (Possible reverting to the Parent BaseField) This happens on the edit item page.

Som开发者_运维百科ething else we noticed is that every time this happens the labels for the fields will display the resouce location instead of the resource value. For example it will display

$Resources:CT_Banner_Name;

Instead of the actual value in the resource.resx file.

Any Ideas?

Usually when I see the $Resources: it's a clear indicator that a feature is missing on one of the load balanced servers. Maybe your custom control references an absolute url or server directly which may cause certain requests to fail?