Alexa, ReSpeaker and Pi Zero wakeword while streaming


I have a Pi Zero with a Respeaker 2mics PiHat. I have Alexa up and running just fine, with KITTAI for wake-word detection. The only time the wake word detection doesn’t work when something is streaming or playing (eg music on TuneIn). I can use my keyboard to trigger Alexa, but not the wake word. If nothing is streaming the wake-word works just fine.

Is this a limitation of the single-core Pi? Or do I need to set up something differently to allow the mic to be listening while the speaker is playing? I’m using the 3.5mm jack for audio.