The signals given are NEC1: {D=133,S=106,F=159} and NEC1: {D=133,S=106,F=158}. perfectly "to the book". These consist of an intro signal, containing the data, then the repeat is just a dumb "ditto", consisting of two impulses. It repeats every 108 ms, so
if you press and hold the volume up button it will blast through from -90 to +10db in a second
means that every send is increasing the volume by 10dB, which sound fairly implausible (or rather silly :-)). Possibly there is a parameter somewhere? (Tech support...)
To literally answer your question, the fifth last number is the duration (in multiples of the modulation frequency) between the intro and the first ditto, and the last number the duration between the dittos. So these are the number you should be manipulating. However, for reasons given before, I severely doubt that it will be the solution you are looking for. There is also a possibility that the device will reject the modified signal.
