I have hit this problem several times. I have a Lexar 1000x CF card as the primary slot and an el cheapo 16GB SD card set to overflow and video recording storage. The SD card pretty much lives there.
I would never have thought this issue was related to having an SD card inserted. I am running the latest firmware but do also recall hitting the issue with the original firmware too.
I would never have thought this issue was related to having an SD card inserted. I am running the latest firmware but do also recall hitting the issue with the original firmware too.