Cavity resonator questions?

Hi friends,

I'm using driven modal soultion & Eigenmode solution for a very simple cavity resonator.

Structure: A cubic air filled cavity
Driven modal: I'm using a coax as an excitation
Eigenmode: Keep the whole structure in the driven modal

Results: For these two types of solution, i have different resonant frequency, they didn't match each other. But i thought it should give the same resonant frequency for both.

Can anybody help me on this? Really appreciate!

maybe your modal has some problems . you can upload the files , someone could help you .

Please see the attached file, i can't get the same result using this modal in both eigenmode and driven modal solutions.
Can anybody tell me where i may have mistake here?
Thank you very much!