Moodle in English

Greeting, I've not seen other reports of this so I'm a bit perplexed, but in at least one of our Grid format courses, the grid images are disappearing. I've only had complaints from one teacher so far and cannot find this in other courses, just one.

We are using:
Moodle 2.5.2+ (Build: 20130913)
Grid 2013110501
PHP 5.3.10-1ubuntu3.7
MySql 5.5.3.2
Any Browser
Theme: Arialist

We have experimented with images large and small, .jpg and .png and different image uploading gui's.

Bottom line, next day, half or more of the 10 sections will have no images and there is no record of images if I look in the inspector, Just says image holder, not URL.

Ideas? Is there something I should look for in the database? Why would img links simply vaporize? I've not seen this in any other way on Moodle 2 or on our site.