I am not seeing those errors in my logs and I send text to my Echo devices daily.
I think you both may need to redo your Echo Speaks cookie setups. The Cookie Authentication Cleared by Device warnings don't seem right. Are your devices showing as online?
Yes, all (13) of my echoes are online and all other text commands to Alexa are working fine. Also, according to my Echo Speaks Tile (@thebearmay), my Echo Speaks cookie on Heroku is up and running as well.
As of yesterday (7 April), these errors have disappeared, and the pistons controlling the voice and music output have started working again. This may have had something to do with the changes that are going on in the background for the new 'Alexa+' initiative that's coming.
I haven't looked into this in detail yet. I don't know if the Now Playing information is available to all echos or just certain ones? I don't recall seeing it on the traditional echos. I just got this echo input to test hanging it off my whole house audio system. It seems to work well and in theory is a much cheaper version of what I am currently doing with my Russound MBX Streamers.
I wrote a driver for the Russound's and I have to listen for updates coming from the player and when I see a new song starting I parse the information coming from the player and refresh the fields.
Presumably the Echo Speaks driver is doing the same thing but either not able to see that it is updated or is not correctly listening for it? I took a quick look at the driver and it is several thousand lines long. So wanted to hang it out there first before I dive in?
I did log a bug in GitHub but the last bug I logged there in January was marked as investigating and nothing since. I am not sure if this is being actively maintained as the GitHub shows no real activity this year and I see @tonesto7 has not posted this year? Maybe I missed something in this long thread about end of support of lower support or something?