Screen snapshot is on , and when i hit the MARK button while in SI mode it saves the waypoint but also says "no mmc/sd card found", so it wont save that screen image. I got it to save an image one time with the same SD card but not anymore, and i deleted that image so there is nothing on the SD card in the unit. i have the HB lakemaster chip and an SD card in the slots. and when i go click on start recording, it says "error recording stopped". what am i doing wrong?