I'm having a frustrating issue with our label printing setup. We're using a Zebra ZD421 printer connected via USB on macOS, along with QZ Tray for print handling and ScanPower for generating labels. The labels are printed in ZPL format, specifically 2.25x1.25 shipping labels.
The problem is that there's a consistent delay of about 7 seconds between printing each label, even when they're triggered back-to-back from ScanPower. I've tried a number of troubleshooting steps, including verifying ScanPower settings, checking QZ Tray logs, and reviewing CUPS logs. I even recreated the printer as a Generic Raw queue and disabled CUPS job history. The delay seems to happen at the OS level, and I'm wondering if there's a way for QZ Tray to either bypass CUPS for direct USB communication or to send multiple ZPL jobs without waiting for job finalization from the macOS print pipeline. This is a critical issue for us as we operate a high-volume fulfillment service. Any suggestions or configurations that could help reduce this delay would be sincerely appreciated!
3 Answers
It sounds like you’ve done a lot of troubleshooting already! However, have you considered bypassing the CUPS setup entirely? When using a standard Mac setup, the direct print functionality seems to eliminate delays. If you’re committed to using QZ Tray, check if there’s a direct USB communication option within its settings. It might require some workarounds, but it could help cut down on that lag you’re experiencing.
The issue could be related to the macOS version you're using. I heard that some updates, particularly recent ones, have affected the print system. If you're using macOS Tahoe, that might be the culprit. If you have access to another Mac, try testing the setup there to see if the lag persists. Sometimes, different models handle printing tasks differently.
Have you checked the length and quality of your USB cable? Sometimes, longer or faulty cables can introduce delays in data transmission. Trying a shorter, high-quality cable could potentially solve your issue.
Related Questions
Can't Load PhpMyadmin On After Server Update
Redirect www to non-www in Apache Conf
How To Check If Your SSL Cert Is SHA 1
Windows TrackPad Gestures