We are using progressive response with python lambda and an AVS device. Though the progressive response is sent immediately (we can verify it from gateway response in our lambda log), it reaches and gets played on device just before the final response.
When we try the same skill with alexa echo or echo dot, the progressive response comes immediately.
Our backend processing takes about 20 seconds and we send progressive response every 5 seconds. Thus we are expecting 3 to 4 progressive responses. However we get progressive response only once on our AVS device as well as on alexa echo or echo dot.
What could be the issues here?