Overview
If a KanexPro AV over IP decoder shows no signal, a black screen, or frozen image, work through the steps below in order. Most issues are caused by network misconfiguration, IGMP settings, or IP addressing conflicts.
Step 1 — Verify Physical Connections
- Encoder HDMI input connected to an active source outputting video.
- Decoder HDMI output connected to a powered display set to the correct input.
- Both devices connected to the same managed switch via Ethernet.
- All Ethernet cables are CAT5e or better; link LEDs lit on both device and switch port.
Step 2 — Verify Network Switch Settings
- IGMP snooping: Must be enabled globally and on the AV VLAN. This is the #1 cause of no signal on first install.
- IGMP querier: Must be enabled on the AV VLAN if no multicast router is present.
- Jumbo frames: JPEG2000 and SDVoE require MTU 9000. Mismatch causes packet fragmentation.
- Flow control: Must be disabled on all AV ports.
- Port speed: JPEG2000/H.265 require 1G; SDVoE requires 10G.
Step 3 — Verify IP Addressing
- Encoder and decoder must be on the same IP subnet.
- Check for IP conflicts — duplicate IPs cause intermittent or no signal.
- Access each device’s web GUI via its IP in a browser. Unreachable = IP conflict or DHCP issue.
Step 4 — Verify Routing Assignment
- If using an IP controller, confirm the encoder is routed to the correct decoder.
- An unassigned decoder shows no signal even on a correctly configured network.
Step 5 — Check HDCP
- HDCP-protected sources require HDCP-capable displays. Test with a non-HDCP source to isolate.
Step 6 — Reboot Sequence
- Power off decoder. Power off encoder. Wait 10 seconds.
- Power on encoder, wait 30 seconds. Power on decoder, wait 30 seconds.
Step 7 — Factory Reset
Reset both devices using the rear panel reset button, then reconfigure via the web GUI.
Still No Signal?
Contact KanexPro support at support@kanexpro.com or 888.975.1368 with: SKU, switch make/model, IGMP and MTU settings, IP addresses of both devices.
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