I'm on a Raspberry Pi 3b which last summer worked well for running Kodi and watching streaming baseball over my fiber optic connection. This summer something is so slow I can't watch it at all, it buffers (the circle) and that's all it ever does. One thing that changed is that I'm using Raspbian Bullseye instead of Buster, and the 2024 version of the MLB program instead of the 2022. My VPN program is Expressvpn. The VPN and MLB are the only things I'm running other than Kodi (usually not even Firefox on here). I'm using a different SD card, whole different Pi installation, same physical Pi.

When I go to fast.com on this Pi I get a reading of 450 Kbps (sometimes it goes up to 10 Mbps). But if I check on a phone connected to the same network I might see 20 Mpbs. My load average is only around 0.5. I was going to blame it on the fiber optic connection, but phones using it work fine. This machine is on a CAT5 connector off the router, phones are on wifi.

What can be slowing it down, what tool do I use to find it?

Has anything else changed, or is it just wifi speed? Have you done a disk check recently? If you're on an sdcard, that has an early 'best-before' date, and you expect failure after that.

Presuming everything is OK, Try changing the orientation of your box for more speed. About 1Mbps will get you a 720p video. Download should be higher. Most Pi owners move to usb wifi dongles because the speed is better. I was driven to move, because I bought a metal box and the aerial saw it as a Faraday shield. European CE approval requires earthing of all external metal.

Another thing you can use is mains powered network adapters. Plug 1 in with the Pi, one with the router and they form a network connection. They also have RJ45 leads, and you plug them into network sockets on router & box. Then connect with your nic, and forget wifi. They're often available secondhand, & cheap.

It seems that just replacing the SD card did the trick, I'll test it more over the next few days. It's a Sandisk "High Performance" one made for dashcam use, but they have only a 2 year warranty. I didn't know SD cards aged this way. I cloned it onto a mostly new SD card and that seems to work in a few minutes of testing. I also wasn't using my VPN.

It wasn't wifi slowness, I have a cat5 cable from the fiber optic router to the Pi's eth0 connector. Kodi shouldn't be trying to write video to the SD so I'm surprised it matters.

"mains powered network adapters?" Do you mean a powered switch/hub like you'd use in a small ethernet network? I've got one of those, not many null modem cables though.

Thank you. If I can watch the game tonight I'll mark this solved. Connected by ssh the load average on the Kodi machine is only 1.24, NASA TV seems to work fine, I ran it an hour or so.

It doesn't work, at least when I'm using the VPN. I used the streaming connection about an hour watching some Nasa TV and old baseball games without VPN and those were fine, but when I turned on the VPN to watch a current game it started buffering within a few seconds, I tried it several times. It only buffers when the VPN is acvive

I’m also posting my saga to the Expreesvpn help/support channel. The suggestion here was to try a different protocol (there are 4 plus auto). But it works fine until a live baseball game comes on, which won’t be until 4 hours from now. I’m not sure this will work as a metric to see if a current protocol is better than another, but I’m thinking of trying to count the number of times it buffers in say 5 minutes, compare that to another protocol.

The 2 most important things I found were (1) use a fresh SD card because they age and get slow and (2) use UDP protocol, not TCP. Maybe last year there was only one choice, use
expressvpn --help
to show all the options. Also at least this year there's a different MLB program, there's something like mlb2022 and mlb2024.

How long an SD card lasts probably depends on the quality, I think you could probably clone your old one and update it once a year or so.

Not that UDP is always preferable to TCP/IP, but TCP has more handshaking and clutter, what we want here is raw speed, we don't care much about errors in individual data bytes.

Thank you so much for the information.