Update once again : Unsure if Amazon added new control options on the Fire Stick or I did not notice them before, but all my connection problems are fixed now after making proper settings under "equipment control", set "Equipment Control" to manual, and make the necessary changes under "Manage Equipment" -> "TV". Love'in my Echo Studio so much more now. Additionally, something new I learned - SPDIF / Toslink fiber optic is PCM and does not feature Dolby DTS Plus, unsure how the Echo studio was working with Dolby DTS Plus through optical input, but maybe that would explain the intermittent issues I had with the optical input.Update: As of March 2024, still love the sound of the Echo Studio, but the HDMI eArc feature is very buggy (Ruko TV, and not a WIFI issue). Actually, the Echo Studio as a whole is very buggy. Even using Aux or Optical input the sound would constantly glitch out regardless of type of cables (I've tried many of both types), seems like firmware glitch 'cause sound comes back after asking Alexa something (waking her up). Please fix this Amazon.Buy it if you have a Firestick and you enjoy rich sound with strong low deep bass in your home theatre experience. The sound is amazing with Dolby Atmos. I only bought one speaker and It is seriously still really GOOD. If you're wondering about stereo with one Echo Studio, YES, there’s still a left and right differentiation even with one speaker. Music doesn’t sound magical unless it has Dolby Atmos, unfortunately Music with Atmos is an extra premium with Amazon Music, but available from other sources.The Echo Studio is about a little larger than a 925g can of coffee (refer to pic), it has good weight to it, and note that it is not magnetically shielded (placing this close to old spinning Hard Drives beware).I spent an entire afternoon experimenting with speaker placement in my living room. I found that placing it in the middle of the room sounds the worst, Bass is weak and will sound like an average speaker in the middle of a room, making it not that much better than an echo.However, very nice sound stage from only one speaker when placed a few inches from the wall under my large screen TV. The bass is magical, REALLY deep bass and sounds seemingly comes from all over the room. The sound from this one speaker is amazingly better than my large 5.1 receiver setup, and I can’t understand how this one small speaker can produce such rich bass even at low volumes. Note the BASS won’t shake the windows or objects, it just sounds rich and deep to the ears. I would describe it as GOOD clean deep solid bass without disturbing the furniture or neighbours.Thinking it was just an over glorified Bluetooth speaker, I felt the price was expensive even when on sale, but this speaker with Atmos is something special. I waited a LONG time before taking the dive to buying it, and due to the HDMI ARC not working with my TV, I was initially disappointed, but happily satisfied when I eventually found a solution (2nd last paragraph).Paring with Firestick was easy, but setting up HDMI ARC was a confusing pain in the ass. Connecting to fibre optic aka SPDIF input is easy, although - will need a proper fibre optic cable to make it work. The Echo Studio puts out excellent sound (Dolby will passes through SPDIF), but no remote volume control, unless maybe if you buy and pair an extra fire remote (haven’t tried)? Bluetooth works, but has to be paired through Alexa app (sometimes a pain in the ass), and sounds flat; pretty much becomes an overpriced Bluetooth speaker, I avoid the Bluetooth connection.If you’re having difficulty with HDMI ARC. where like me, you have the FireSTick on an HDMI Switch, and you have all the settings correct, but sound only works on FireStick and every other device is silent - try connecting the FireStick by itself directly to the HDMI ARC input on TV, and connecting the other devices on the HDMI switch to ANOTHER HDMI input on the TV. This solved my no sound problems with HDMI ARC. Yes, you might have more crap up behind the TV and have to switch sources with TV HDMI instead of the HDMI switch, but it’s a sacrifice I’m willing to take in order to use the Echo Studio with all my other devices.I no longer regret buying the Echo Studio, and I can’t stop using it. Constantly wondering if I should sacrifice two weeks groceries for a second unit to experience the expanded stereo sound stage, and wondering how two Echo Studios would work with SPDIF input???