Anyone else having issues with Data Series in Simple Chart widgets?

Hi all,
After a few months of working smoothly, suddenly over the last 2 weeks our widgets that include a Data Series are no longer working. We've applied a Drill Down Hierarchy as the Data Series and it's like the mapping between the levels is broken when clicking on a data point to filter. The first level drill down works perfectly but the lowest level drill down will apply a filter for something completely different to what you clicked on!
The page filters are still working as they should but clicking a data point in the widget is not working (and giving us plenty of errors in the process!).
I've logged a job with support and they don't seem to have any solutions at the moment so just wondering if anyone else is experiencing this. It's happened on a few of our dashboards so not an isolated incident unfortunately!
Cheers,
Ashleigh