Slow Studio Network? A 15 Minute Checklist

Everything feels slow: files open late, timelines stutter, uploads crawl. Before anyone replaces equipment or restarts the switch, spend fifteen minutes finding out where the slowness lives. This checklist needs no special skills and almost no tools. It sorts the problem into one of four places: the cable and link, the network between machines, the NAS or server, or the application on one computer.

Tool notes: the commands are standard in Windows and macOS. iperf3 is a free network test whose options are documented in its manual. Menu names for NAS and switch screens vary by brand, so use the names here as a guide to what to look for.

The quickest first thing to try

Ask one question: is it slow for one person or for everyone? If one computer, check that computer's cable, port and settings first. If everyone, the cause is likely shared: the NAS, the switch, the internet connection or something running on the network. That single answer halves the list.

The 15 minutes, step by step

1. 1Minutes 0 to 2: write it down. Note the symptom, who sees it, what time it began, and what changed recently (new equipment, updates, a new person, a long backup, a cable moved). A written note stops the investigation from going in circles.
2. 2Minutes 2 to 4: isolate. Check if it is slow on one computer or many, in one app or all apps, with one share or all. Try the same task on a second computer. Try a different file.
3. 3Minutes 4 to 6: read the link speed. On Windows, Settings, Network and internet, Ethernet shows it. On a Mac, System Settings, Network, your Ethernet service, Details, Hardware shows speed and MTU in recent versions of macOS. A 10 Gb connection reporting 1 Gb is a finding. Repeat for the NAS. Make sure Wi-Fi is off on machines that should be wired.
4. 4Minutes 6 to 8: test latency and loss. Run ping to the router and then to the NAS, 50 times. On Windows: ping -n 50 followed by the address. On a Mac: ping -c 50 followed by the address. You want zero packet loss and steady times. Packet loss or large jumps in response time point to a cable, port or a congested link.
5. 5Minutes 8 to 11: measure raw network speed with iperf3. Run iperf3 -s on one machine and iperf3 -c with that machine's address on another, with -t 30. Then add -P 4, and then -R for the reverse direction. This test does not touch any disk, so it shows what the network alone can do. Our 10GbE troubleshooting guide explains the options.
6. 6Minutes 11 to 13: copy a large file. Copy a single large file from the NAS to the computer and back, and note the time. On a Mac, the Blackmagic Disk Speed Test app, available free from the Mac App Store, can measure a local drive. Compare the NAS copy with a copy on the local SSD.
7. 7Minutes 13 to 14: look at the NAS. Open its resource monitor and storage manager. Look for high CPU, high disk activity, a RAID rebuild or scrub in progress, a backup or snapshot job, a volume that is nearly full, or a disk reporting errors. Note who is connected.
8. 8Minutes 14 to 15: look at the switch and cables. Check port lights and the switch status page for the ports involved. Look for ports that negotiated a lower speed, error counters that keep rising, and the uplink between switches. Check the physical cables for kinks, loose plugs and cheap patch leads.

How to read the results

• iperf3 is slow, link speed is low or ping shows loss. The problem is the network path: cable, port, adapter or switch. Swap the cable and port first.
• iperf3 is fast, file copies are slow. The network is healthy. Look at the NAS disks, how full the volume is, SMB settings, and the computer. See our Premiere dropped frames article for the SMB side.
• iperf3 and copies are fine, but one app is slow. The problem is on the computer: cache location, decoding, effects or a setting. Start with the playback stutter guide.
• Everything is fine in the daytime test but slow at certain times. Look for scheduled jobs on the NAS, backups, sync tools or heavy use by other people.
• Only internet-bound tasks are slow. Run a speed test and look at the internet plan and router. Our Frame.io upload guide covers uploads.

What not to do

• Do not restart the switch or NAS in the middle of the working day without telling people. Open files can be damaged.
• Do not change several settings at once. You lose the evidence of what helped.
• Do not buy new equipment before you have run iperf3 and a cable swap.
• Do not skip the written note. When you ask for help, it saves time.
• Do not ignore a disk warning on the NAS. Check your backups first, as in our backup strategy for video production.

When it is time to call someone

Call for help if the checklist points to the switch or NAS and you cannot change it safely, if the problem comes and goes with no pattern, if a drive is failing, if several machines are affected after a change, or if you have no idea what is on the network. A person with the right tools can check the whole path in one visit. Our guide to setting up a small studio network describes what a sound design looks like.

Want a person to look at it?

This is the kind of problem our production consulting team handles: reviewing the network, storage and workstations together and writing down what to fix first. See our infrastructure audit service, or tell us what is happening in your edit bay and a real person on our team will reply.