What should I do if the print quality is poor or the printer feeds labels incorrectly?

If the print quality is poor or the printer feeds labels incorrectly, please update the printer firmware first, and then calibrate the label sensor.

Step 1: Contact MUNBYN Technical Support

Firmware updates for the RW402B are sent individually according to the printer's serial number (SN). Please contact our technical support team and provide the SN before attempting the update.

You can provide the SN in either of the following ways:

1. Send us the SN shown in the Settings page of the Munbyn Print app.
2. Tap “Print Self-Test Page” in the app's Settings page, and send us a clear photo of the printed self-test page.

Please contact us by email at support@munbyn.com, or by WhatsApp at +86 178 1788 1067. Scan the QR code below for more contact details:

Please also briefly describe the print-quality or paper-feeding issue you are experiencing. Our technical support team will identify your printer and send the appropriate firmware update directly to your device.

Step 2: Update the firmware in the Munbyn Print app

After receiving confirmation that the firmware has been sent to your printer:

1. Power on the printer and open the Munbyn Print app.
2. Connect the app to your RW402B printer.

3. When the printer status shows “Connected,” tap “Settings.”

   

4. A “Firmware Upgrade (1.2.1)” pop-up will appear. Tap “Upgrade” to start the update.

   

5. Wait until the firmware update is completed.

Step 3: Calibrate the label sensor

1. Power off the printer completely, and make sure no paper is loaded inside the printer.
2. Press and hold the FEED button. Keep holding the button while powering on the printer.
3. Release the FEED button immediately once you hear a beep.
4. The printer will run automatically after you release the button.
5. When the printer stops running automatically, wait for 5 seconds.
6. Restart the printer, load the label paper, and test printing again.