Echo won't make a sound!

[albatrossblue]

Hi all,

I have an Echo and a Echo Dot.  I am a premium user.  My Echoes have just stopped playing spotify at all.  They appear to be connected, claim to be connected, but just don't make a noise.  I have tried unlinking and relinking my account, different browsers, using the app on my phone, and swearing at it.  Please could you make some suggestions as to how I could fix it?  

Thank you