I have the same problem, and I did the things that you said, but the print still grainy the pictures and the quality is awful. I bought it two weeks ago and the first pictures was ok, but now I don’t know what happened. I’m not in the same place where I bought it, so what can I do?
Let us first try updating the firmware on your HP Sprocket:
HP regularly releases firmware updates. Upgrading the firmware might resolve the issue.
Make sure the Sprocket is on and your mobile device is connected to the Internet.
On your mobile device, open the HP sprocket app.
Tap the Menu icon , and then tap sprocket.
Tap Manage Printers, make sure your Sprocket is selected, and then tap Printer Settings.
Under the Status section, locate Battery.
If the battery charge is 25% or higher, continue with these steps.
If the battery charge is 24% or lower, charge the battery for at least 30 minutes, and then continue with these steps.
In Printer Settings, look for a firmware upgrade.
If a firmware upgrade displays, tap Get Firmware Upgrade and then follow the on-screen prompts to complete the update.
If a firmware upgrade option does not display, the firmware is up-to-date.
Try printing and is the issue persists, follow the steps below to clean the paper feed rollers:
Dirt and debris on the paper path rollers can cause print quality issues. Use the colored Print Quality Card (formerly the Smartsheet) from the same pack of HP ZINK photo paper currently in the Sprocket to clean the paper path rollers.
Remove the paper cover, and then remove any photo paper from the input tray.
Check the photo paper and remove any severely bent, wrinkled, or torn photo paper from the stack.
Reload the photo paper with the colored card on the bottom of the stack with the barcode facing down.
Replace the paper cover, and then send a print job.
The Sprocket calibrates and cleans the paper path rollers with the colored card, and then prints the photo.
Let me know if this helps.
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