[Xastir] Noisy conditions

[Skyler F]

I set up a USB sound card with soundmodem (I could not figure out direwolf) and started decoding packets. I was told that packets can be decoded in noisier environments then standard FM voice, but that isn't showing to be true. 

Here is a MP3 file of two packets. The first one was not decoded and the second one was decoded by sound modem. They both seem pretty clear noise wise however, and I want my station to decode as well as possible when it is put into use. 

I am using speaker audio from an alinco dr-600. 

http://amsatnet.info/recordings/APRS.mp3

If it is not decoding like it should, are there simple improvements?

The recordings are exactly what the computer hears. 

Thanks,
Skyler KD0WHB