Tuning PC performance for Zoom dancing

Note:  Orginally written to help people improve sync in Zoom dances,  these tips are actually more general and apply to both dancers and dance leaders with or without shared computer sound.

There can be several problems that occur with a zoom dance session, but the most annoying is when the music and the steps are not synchronized.   This only happens when the dance leader is sharing computer sound.   (But it is nearly impossible to get great music without sharing computer sound.  More in the appendix.)   

If there’s something missing from this guide, email jnjbloom@gmail.com with your questions or suggestions.   My experience is with a Windows PC, so if anyone has contributions relevant to other platforms let me know.

There are several different things that can cause bad synchronization.  I’ll start with the most common, and discuss what can be done about it.

#1  Your PC’s connection to the internet isn’t performing well.
- Start by testing your internet connection.  I use www.speedtest.net   Ideally you would have a latency (ping) of 15 ms or less, and a download speed of 10 Mbps or more.    If not, you may need to upgrade your internet plan.
- If you are connecting via WiFi, see if you can use an ethernet cable to connect to your router or cable modem.   If your PC does not have an ethernet port, you may need an adapter.   This usually makes Zoom  much better.
- Other applications on your PC that have heavy internet use should be paused.  This includes DropBox (pause synchronization), cloud backups such as Carbonite (can also be paused), etc.   For me this makes a huge difference.
- Try to minimize other people or devices in your house connected to the internet. Phones, tablets, or other computers should be turned off or put to sleep.  Your DVR should not be recording.  Etc.

#2 Busy CPU  If your computer is trying to do a lot of other things in addition to running Zoom, that can affect your audio or your video, or how they are synchronized.  Things that have worked for others are to pause the anti-virus program, suspend automatic disk defragmentation.   (thing like backup mentioned in #1 can also cause busy CPU).  Close any programs you don’t need.

Tools for assessing your system:  While running Zoom, the Audio Settings pane (click the up arrow next to the microphone) also can show "Statistics".   The "Overall" tab will tell you if the CPU is busy (Overall should be 40% or less).   The Audio and Video tab will show network issues - any Packet Loss is bad, and latency should be under 40 ms.   

The ultimate tool on Windows for assessing exactly what is using system resouces is Task Manager, which can show CPU, Disk, and Network utilization.   My PC has 145 different processes running (but only because I cleaned it up – it used to be closer to 200).    You can sort by CPU to see which processes are using a lot of CPU, which is usually the problem.

Mac’s have an equivalent tool called Activity Manager.

For more advanced readers, consider uninstalling programs you don’t ever use.  PCs these days come with lots of junk installed and some of it runs in the background.  Don’t uninstall things you don’t understand (Google them first).    There may also be programs you use rarely that don’t need to be started when you boot your computer.

Another advanced tip – raise the priority of Zoom.   In Task Manager, click on the Details tab, and then right-click on Zoom and Set Priority – Above Normal should be enough (do Not choose realtime).