Hello TimboZ,
There is no option to rollback the firmware at our service centers unfortunately. You may want to try cleaning the contacts on the camera and lens with a clean, dry, microfiber cloth to ensure good communication between them. I would recommend starting with that. I would also suggest removing any lens filter that may be attached to the front of the lens since certain lens filters may sometimes interfere with the camera's auto focusing system. Does your camera work properly with other lenses? Try cleaning the battery contacts with a clean, soft microfiber cloth as well. Dirty contacts could cause an issue like this. Do not use any kind of solution when trying this.
In terms of the playback issue, you can also clean the contacts on the memory card as well with the microfiber cloth. Have you tried formatting the card in the camera? I would recommend trying that as well. When the card is formatted, all images and data on the card will be erased. Even protected images will be erased, so make sure there is nothing you need to keep. If necessary, transfer the images and data to a computer, etc., before formatting the card. You will find [Format] in the yellow Wrench menu tab #1. Make sure that you select the correct card when doing this. Finally, let's try using a different lens and card.
