Diagnosis
The loud gurgling or bubbling noise is almost certainly normal operation for your Frigidaire FFAD2233W1. It's the sound of liquid refrigerant flowing and evaporating through the system's coils and compressor, a core part of the dehumidification process. This is most common right after the compressor starts or just after it shuts off.
How to Fix It
No repair is needed. To minimize concern, you can ensure the unit is operating correctly: verify it's collecting water into the bucket and that the "Bucket Full" light isn't on. The noise is simply an auditory indicator that the refrigeration cycle is active and removing moisture from the air.
If That Didn't Work
If the noise changes to a persistent loud knocking, grinding, or metallic rattling, that indicates a different issue. First, ensure the dehumidifier is on a firm, level surface and that the water bucket is clicked completely into place. A persistent rattling could mean a loose component inside the casing or a problem with the fan. In these cases, unplug the unit and contact Frigidaire support.
Heads Up
The gurgling will often be louder when the unit is working hardest in a very humid room, as the refrigerant is cycling more rapidly. This is typical and not a sign of a problem.