It seems the part that connects to the amp are too far inside the IEC.
I’ve never been a fan IEC connectors. It’s a poor design, IMO.
What is the Amplifier? Manufacturer and model?
How deep is the well of the IEC inlet connector (on the Amp), the IEC female connector plugs into? When you push the female connector onto the male blades, prongs, of the inlet connector does the shoulder on the female connector come up tight against the outer flange of the inlet connector, therein maybe not bottoming out against the back of the inlet connector?
OR, is there a space between shoulder of the female IEC connector and the outer flange of the inlet connector? Therein the female connector is bottoming out against the back of the male inlet IEC connector.
If you measure the length of the inlet connector blades, prongs, from the back of the connector to the front of the blades,
Then measure how far back inside the female connector where the actual female contacts start you can then determine how much overlap there actually is for the male blades and female contacts.
Looking inside a FURUTECH F1-11 CU female connector the contacts look to be recessed back about 3/16". Must be a NEMA safety thing.
The three most important things for a good electrical connection:
Cleanliness.
Conductor, contacts, surface area.
Contact pressure.
.
