IR extender incompatibilities

I've found that the remote with my Z9XPro doesn't work with my IR extender. IR remotes I gather transmit with a carrier frequency of which there are two common of 38KHz and 56KHz, but its possible to use other.

My working assumption is my IR extender is 38/56KHz compatible with dual receive diodes but the Zidoo remote is on a different carrier frequency. I've seen a note it uses NEC1 IR codes and I think its possible for some NEC1 devices to also be on 40KHz. So, my guess is the Zidoo remotes are 40KHz

And just to confirm, yes the IR transmitter from the extender is over the receive diode on the left hand side of the players front panel

Anyone seen anything similar with other extenders for the Zidoo remotes? Anyone confirm my assumption?

Thanks

 

Had no trouble with IR on my Crestron system, either generating a set of standard NEC codes or learning from the remote itself.

The carrier frequency is 38.02886KHz.