A: No. If the knob spins freely without changing frequencies, the optical encoder is physically broken. A reset will not help.
If "GX3800" was a typo for a Grundig Smart TV (like the GX series), here are the verified codes for a (Service Menu): grundig gx3800 factory reset code verified
No. A factory reset removes software locks, but it cannot bypass subscription-based encryption. You still need a valid CAM module and card. If "GX3800" was a typo for a Grundig
Reviewers and users generally find the reset process straightforward but note a few critical points: Reviewers and users generally find the reset process
instructions for this model to see if that resolves your technical issue? GX-3800 - User Manual
Changing settings here can brick your phone. Do not use this unless a technician has specifically told you to.
If your device is none of the above, please clarify the device type (Radio, TV, Appliance) and I can provide the exact code.