Trouble sending IR volume control using Arduino

I am currently trying to make a simplified IR remote control device for my McIntosh C2300 preamp.
I am using an arduino and the IRemote library.
The preamp uses the NEC protocol and, using IRrecvDump, I got the following codes for the keys I need:

Decoded NEC: 53AA43BC (32 bits)

Decoded NEC: 53AAC33C (32 bits)

Decoded NEC: 53AA639C (32 bits)

Decoded NEC: 53AAC936 (32 bits)

Decoded NEC: 53AA49B6 (32 bits)

Decoded NEC : 53AA03FC (32 bits)

Using the irsend.sendNEC() from the same library and an IR LED, I can send control the preamp to power on/off, mute and change inputs without any problem.
But I can't manage to change volume up or down, no matter if I send the command repeatedly and/or I use the repeat argument :

irsend.sendNEC(0x53AA43BC , 32, 3);

I also have the D100 DAC from the same brand, which has a volume control which works properly when provided the appropriate codes.
I also tried with an ESP32 with the no better results.
Any idea?
Thanks in advance.

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.