by default the gain is set to -10 which is normally way too high.
Instructions can be found in this thread:
Good starting values are 49.6, 48.0, 44.5
Be aware to remove the “-” in front of it. this character is used only in “-10” which is a special setting. All other values do not use it.
Normally you’re not going below 40 if you do not have an active antenna or special amplifier connected.