Moodle suddenly won't record new attempts on old O9 Quizzes
I've been using Quizmaker 09 with Moodle for a while without any problems. I have the setting so that students can retake a quiz as often as they wish, and the highest attempt is registered in the gradebook. The setting are such that students are forced to begin a new attempt. Until quite recently, this worked perfectly fine: one student took a quiz 10 ten times, and Moodle registered each attempt. Within the last week or so, Moodle suddenly stopped recording new attempts on some -- but not all -- quizzes. The new attempt simply doesn't register. I've confirmed this on both a Mac (Mavericks) and a PC (Windows 7), using IE, Chrome, Firefox, and Safari. What makes this even more curious is that if I upload the same quiz as a new Scorm, it seems to work fine (multiple attempts are recognized: but since multiple attempts were once recognized on the old quizzes, I'm not sure whether it will last). However, I need to create a new SCORM package on the Moodle site: merely replacing the old quiz with a newly published quiz doesn't work.
I've asked the tech people at my uni whether there was some kind of update to Moodle that may have caused the problem. It sounds to me as if it is a Moodle issue, but I was wondering whether anyone else experienced similar difficulties.