Fix slow or choppy video

Symptoms

• Your clicks and typing show up late on the remote screen.
• The picture stutters, freezes for a moment, or jumps.
• The picture is blurry or in black and white.

Read the status strip

The strip along the bottom of the viewer shows live numbers for the screen you are watching:

• the frame rate (fps) and the video bit rate,
• download and upload speed (↓ and ↑),
• ms rtt: the round trip time of the connection. Lower is better.
• +N ms buffer: extra delay Blink adds to smooth over network hiccups. It grows after a hiccup and shrinks after a quiet minute.
• N lost: packets lost on the way. It only shows when some are lost.

A high round trip time points to a slow or distant connection. A growing lost count points to a congested or unreliable network, often Wi-Fi.

Pick a quality setting

The quality menu in the viewer toolbar has four settings. Every session starts on auto, and a manual choice lasts until you close the viewer.

Setting	What you get
auto	Blink adjusts frame rate, sharpness and colour to the connection as it changes.
low	15 frames per second at half resolution, in black and white. Easiest on a poor connection, and text stays readable.
standard	30 frames per second at full resolution.
high	Up to 60 frames per second (or the monitor’s refresh rate) at full resolution. Needs a fast connection.

If the picture turns grey or blurry on auto, that is Blink saving bandwidth on a weak connection. Choose standard or high only when the connection can carry it.

Check the network

1. Close other heavy traffic on both sides: large downloads, cloud backups, video calls.
2. Ask the customer to move closer to their Wi-Fi router or use a cable.
3. Each monitor you watch, in the viewer or in pop-out windows, is a separate video stream. Watch only the screens you need.
4. Try your side from another network. If it is better there, your network is the bottleneck.

Direct or relayed

Blink connects video directly when the networks allow it. When a firewall blocks the direct route, for example a network that blocks UDP, Blink relays the session instead. A relayed session works, but it usually adds delay.

• Blink Cloud: relaying is handled for you. If sessions with one customer are always slow, ask them whether their network blocks outgoing UDP traffic.
• Your own Blink server: make sure the session and relay ports are open on the server (see Fix a Blink agent that will not connect), so sessions do not have to fall back to relaying over TLS.

Check the remote computer

1. In Sessions, open the session and look at Encoder under Remote computer. openh264 means the computer is encoding video in software, which uses more of its processor and can slow things down on an older computer. See Fix a black screen or missing video for graphics driver advice.
2. Ask the customer to close programs that keep the processor busy.

When to contact IZT

Contact IZT if sessions stay slow on a good connection on both sides. Send the session id, the time, and the numbers from the status strip. See Collect logs for IZT support.