We would like to report an error from the customer machine with serial number 143503328. We took out the sensor and tested it on our demo machine with serial number 143503052. When banknotes are placed in the singler, after sensor self test the error message shows, “error during sensor test, sensor system soiled, clean felt info: sensor system soiled, clean felt (#8301, Opt 506)”. Then the banknotes does not start singling, if you want to clear the error message you need to take out the banknotes from the singler.