OK, so I tried the additional suggestions and saw nothing but unexpected results. I decided I'd uninstall Mappero (had to uninstall Mappero to remove the others), Extra Decoders and OGG Support using the uninstall App. Manager GUI. I then reinstalled all three (including the latest updated OGG Support version) and problem gone. Someplayer and Symfonie both working well now with the latest OGG update.