I understand this is an old thread, but since it's just about the only page on the Internet that mentions Audio-gd and IR codes I will post my experience here.
All relevant links at the bottom.
I was looking for a way to control my Audio-gd Precision 1 amplifier with my Samsung Galaxy S4. First I contacted Kingwa at Audio-gd, and he provided me with NEC-codes for the Precision 1. I translated them to pronto codes with IrScrutinizer, but it didn't work. I figured it was the wrong codes, so I went back to Kingwa, but he wasn't able to help me.
Long story short I ended up concluding, that if I wanted this feature I had to somehow capture the signals from the remote itself. I purchased the parts for building a "Arduino Nano as IR sender and receiver", and together with IrScrutinizer it did the job.
With the codes and a combination of the android apps "Unified remote" and "Tasker" i ended up with a remote looking like the one I linked to below.
IrSrutinizer: http://www.harctoolbox.org/downloads/index.html
Thread at remotecentral.com: http://www.remotecentral.com/cgi-bin/mboard/rc-theater/thread.cgi?4898#1316358
Arduino Nano as IR sender and receiver: http://www.harctoolbox.org/arduino_nano.html
Unified remote: https://www.unifiedremote.com/
Tasker: http://tasker.dinglisch.net/
NEC and Pronto codes for the Precision 1: http://tinyurl.com/hch8nmx
Picture of Tasker remote: http://tinyurl.com/hgsxe4k
Tasker remote export: http://tinyurl.com/hgsxe4k