Effect of Internet Service Quality on Streaming?

ADSL/DSL runs over copper pair phone lines. Ever see the connections in Krone boxes using blades? The diodic interface there alone can’t be good. Have you tried cable or fibre?

First, @noromance covers it pretty much.  ADSL/DSL is like 30 year old technology with extremely limited bandwidth.  I'm not really concerned with the physical connections, but the back switches and routers on those circuits are probably just as old and will never be upgraded.  Consider cable, fiber or 5G based Internet as a much better options.

Generally speaking though, most streamers have enough buffers that they can ignore normal internet latencies, but not errors and reconnects.  Roon for instance has the ability to choose how much of a streaming buffer you use to try to eliminate this issue. 

Next, if possible, avoid Wifi streaming.  If it's not possible to avoid it, use a phone or laptop Wifi analyzer app to ensure your router is on an unused channel.

As an experiment you can put some FLAC or HiRes files on a USB stick and play from that during the times when you are getting worse quality.  If that does not suffer from the quality issues you know it is likely not the power but is your connection instead.

I’ve never bought the AC noise explanation. I have an oscilloscope and it doesn’t change much day to night and an good power regenerator cleans it up anyway.

You can check if it is your internet by just trying a CD in a transport using the same DAC.

I think often it is ambient noise. We often don’t realize how much ambient noise is coming from both inside and outside the home.

Jerry

Regarding DSL: I am on DSL from Century link. There is a fiber trunc 2 blocks from my house from there its phone line to house. I pay for 50 Mbps and just tested it and I am getting around 60 Mbps down load. Only outage I have ever had is when squirrel nested in line pack. After some upgrades to my streaming stack i have near the same SQ as my Rega P6/AniaPro/decentphonostage. I occasionally get drops but its tolerable. I work from home on a Secure VPN , stream tv and music all the while. Occasionally I have to upload large software installations to remote servers albeit slow, taking hours , its consistently solid.