The codes you posted are NEC1 protocol.
AV1 = Device 4 function 90
AV2 = Device 4 function 208

The easiest way to find AV3 is to use MakeHex to generate all 256 hex codes for your device and search for it.

[Link: hifi-remote.com]

you will need this to,

[Link: hifi-remote.com]

and

[Link: remotecentral.com]

Or I can email you a ccf for you to try.