Help with offline speech recognition in a Raspberry Pi • /r/MachineLearning

As part of my project I need to implement offline speech recognition in a Raspberry Pi 3. Doing some research I have found the CMUSphinx project (http://cmusphinx.sourceforge.net/wiki/tutorial) I tried it for simple command and control and it is awesome, however, when I move to real conversations, I found it to perform very bad. I have a small corpus of about 500K utterances, and trained ARPA models with it. With some parameter tuning I can get some improvement but very far from good. Notice that I am using the pre-packaged acoustic models and I am just tinkering with the language models.