DAC power on - Information about connected client via websocket

Help and Support Help
, ,
1

Hello everyone!

I would like to ask for your help with the following:

Long story short:
Is there a way to access information over WebSocket about whether an Android, iOS, or web client has connected to the Volumio server?

Long version:
I’m new to the Volumio community. Over the past month, I put together an audio player using a Raspberry Pi 3B and a Khadas Tone Board. The setup includes a toroidal transformer and two stabilized power supplies in the enclosure. The Tone Board’s power supply only turns on when the Pi starts and 5V appears on the USB output. I use the Amplifier Switch plugin to power on the amplifier, and the Rotary Encoder II plugin manages an EC11 rotary encoder. The Amplifier Switch controls an SSR via GPIO, which is installed inside the amplifier. Everything works well, and I’m grateful to the developers!

However, I also have an SMSL DL200 DAC, which has noticeably better sound quality. I’d like to switch to using this DAC instead of the Tone Board, but I don’t want to turn the DAC on and off manually. I need automated switching, similar to what I have with the amplifier. Unfortunately, the Amplifier Switch solution isn’t viable here because, understandably, Volumio throws an error when playback is attempted but the DAC isn’t yet accessible.

I tried researching what information can be accessed via WebSocket. In my opinion, a good DAC activation trigger could be when an Android/iOS/web client connects to the Volumio server. So far, however, I haven’t been able to retrieve this information over WebSocket. Does anyone have a solution or suggestion for this? Volumio runs 24/7, and music playback is controlled from phones or tablets, with only the rotary encoder and push button on the player itself.

Thank you in advance for any responses!
br
csuti

2

update:
I found what I was looking for in the Volumio logs, but unfortunately, I cannot access it via websocket at the moment. I am working on an alternative solution, and once it’s completed, I will publish it here in case someone is looking for something similar.

Oct 30 21:41:51 volumio volumio[900]: verbose: New Socket.io Connection to X.X.X.X from X.X.X.X UA: Mozilla/5.0 (iPhone; CPU iPhone OS 18_0_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/15E148 Engine version: 3 Transport: polling Total Clients: 8

3

I finally found the solution, not websocket, but it works!
A Python script continuously monitors the Volumio log. I defined what signifies a new client connection in the logs (iOS, Android, Windows), what is considered play, and what indicates pause/stop statuses. The script runs as a Raspbian service. When a new connection occurs, a GPIO pin is set high, and it sends the power-on signal to the SMSL DL200 DAC via LIRC. At this point, a 20-minute timer starts, after which the DAC will turn off if there is no play action. If play is followed by pause/stop, the timer still starts and will turn off the DAC if there is no play again. I monitored the recurrence of new connections, and a repeated infrared power signal can only turn on the DAC after the timer expires. With this solution, the DAC connected via USB is powered on with the client connected to Volumio, and the amplifier switch turns on the amplifier (not infrared), so the entire sound system powers on and switches off during inactivity.

1 Like