Here is the link for the K2 Item modal and this problem:
www.quebecguitare.ca/professeurs/montreal/daniel

Step to reproduce problem:
-Click on this link: www.quebecguitare.ca/professeurs/montreal/daniel
-Click on the K2 Image
-Look at the link at the bottom of the image
-Voilà

Regards.

This title is generated from the link's title attribute. You can change this to the item's title or something custom.

Hi Krikor, I do not understand your last reply.

Could you give more details?
Thank you
Regards

Open the item.php of that subtemplate. and locate title="<?php echo JText::_('K2_CLICK_TO_PREVIEW_IMAGE'); ?>"

This is what generates this title. You can change this to the item's title or a custom search.