Here's a workaround.
Every Echo device has the ability to play a sound at the start of a request. Just turn that option on in the Alexa app.
After that is done, when you start speaking to Alexa, just pause for a couple of seconds before you ask the question. The sound will probably wake up your speakers. You would ask something like this: "Alexa, (pause for 2 seconds) What is the weather today?"