Google Voice Stopped Working. Please Help.

Google voice stopped responding to "OK Google". I have an HTC One M8 with Android 5.0.1. I don't think it is a hardware issue because it works if I tap the microphone icon. I spoke with Verizon support and after deleting caches and data we did a factory reset. When the phone starting working again, so did Google Voice. After a few minutes, it stopped again. When it stops, I go into settings to try and retrain the voice. That had worked before. Now, when I start retraining, the first "Listening" is highlighted with the blue spinning circle. No matter what I say, that doesn't respond and move to the 2nd "listening". It might be another app because everytime I restart the phone, "OK Google" works for the first 30 seconds then stops. I've tried disabling the apps that could use the microphone, but that didn't help. I would greatly appreciate any help. Thank you in advance, Dr. Mark W. HelfandHTC One M8Android 5.0.1Not Rooted