I can find a DMP A6 streamer: https://www.hifistudio79.nl/product/eversolo-dmp-6/
Is this what you are using? And you are connecting to your Sonos Five or Play 5?
Have you tried playing with the Line-In Source Level? https://support.sonos.com/en-gb/article/adjust-line-in-settings
I have to ask, though, assuming you’re referring to the DMP-A6 streamer, why are you doing this?
I can find a DMP A6 streamer: https://www.hifistudio79.nl/product/eversolo-dmp-6/
Is this what you are using? And you are connecting to your Sonos Five or Play 5?
Yes, the Eversolo with a pair of 5,s
I’ve not investigated this, but does the streamer not have a line level output? A preamp is only needed to get low level outputs (mostly found on turntables) to line level. I do not think a streamer would need a preamp. If you think the volume from the streamer is too low, have you tried different input settings for you Five? You can change this in the Sonos app.