Needs to be rastarted after every print command

Hi, i kindly ask for help with problem with my printer R-400 plus. I think i did all could to help (reinstalling drivers (argox driver as well as seagull), reseting printer to factory defaults, checking settings and so on). Label sensor is clean. Description of process: I turn on the printer. All LEDs (ready, media, ribbon) are lighting. I command printer to print e.g. 2 labels and it goes well. But once it is printed, LEDs "ready" and "ribbon" start to blink at same tempo and dialog caution window is showed("Ribbon out. Caution. Please check ribbon supply"). But there is no problem with ribbon. At this time I cannot command (in Agrobar or Bartender) to print another labels - it does nothing. When cancel button is pressed, it prints only one label and another two blank labels are pulled out. (I add that no there are no documents waiting in queue to be printed). At this time printer must be restarted (turn off and on again). Can you please give me suggestion how to fix this problem? Thank you very much Radek Pospisil