I've run a 296 for the last five years and never had any problem. You could phone or e-mail your local Aviation Authority (I see that you are in the Netherlands) and ask them if there has been, co-incident with your problem, any temporary degrading of the Sat/Nav system.
When that happens here in Britain, we generally get an advance warning. It is a good idea to carry a handheld backup just in case you have a failure of your prime instrument.