Hello,
Not sure why but the permissions on /opt/kaltura/app/cache are wrong.
Running:
# chown -R apache.kaltura /opt/kaltura/app/cache
# find /opt/kaltura/app/cache/ -type f -exec chmod 660 {} \;
# find /opt/kaltura/app/cache/ -type d -exec chmod 775 {} \;
Should straighten it up.