The USGS did a URL change for the GeoJSON feed used by the script.
The quake-json.php script V1.07 (2-Jun-2015) fixes the issue of a feed URL change.
Standalone users: download from the script page
V3 Template users: use the update tool for Base-, Plugin-, 2-Jun-2015
Only the version info and the URL for the GeoJSON feed changed in the script. After install, run the page with the quake-json.php with ?cache=no to refresh the cache with the new feed.
I updated my parents site to use the new json script since they were still using the old outdated script. It’s working fine, but the markers aren’t showing on the map. i.e… there town, or close quakes.