I finally had a chance to do more testing today and found something unexpected. I used the code from the sample app to dump the mic levels to the console while pocket sphinx is working.
The typical patter was this: silence ( approx -100 DB ) followed by a peak of anywhere from -80 DB to -65 DB and then either a message from pocket sphinx saying “speech detected” followed by the hypothesis, etc. OR no message “speech detected” followed by no other messages from pocket sphinx.
At approximately -76 DB and above the results were good, below -76 DB is where consistency started to drop off.
So, to summarize the problem I’m seeing doesn’t seem to be the accuracy of the word identification, but rather the threshold for whatever causes pocket sphinx to generate a “speech detected” is higher than what I would like.
I looked through the API documentation again but did not see the option to adjust that. Any suggestions appreciated.