Got it also working with only one Switch (Linksys) with the following configuration:
| Port 1 | Port 2 | Port 3 | Port 4 | Port 5 | |
|---|---|---|---|---|---|
| Audio Protocol | RoonRaat | RoonRaat | RoonRaat | Devialet AIR | n.a. |
| Description | Repeater | D220 Pro | Media Server | Video Renderer | TV |
| Port Speed | 1 Gb | 100 Mb | 1 Gb | 1 Gb | 100 Mb |
| Duplex Mode | Full | Full | Full | Full | Full |
| Multicast Router Port | Static | none | none | none | none |
| Auto Negotiation | Disabled | Disabled | Enabled | Enabled | Enabled |
| Flow Control | Enabled | Enabled | Disabled | Disabled | Disabled |
| IGMP Snooping | Disabled | Disabled | Disabled | Disabled | Disabled |
| MLD Snooping | Disabled | Disabled | Disabled | Disabled | Disabled |
| Jumbo Frames | Disabled | Disabled | Disabled | Disabled | Disabled |
The key parameter to change, to get it working with only one switch, was to configure the port to the Repeater->Router with Auto Negotiation=Disabled and Flow Control = Enabled.
I am very happy now because also Devialet AIR with JRMC (Media Server & Video Renderer) works perfectly without any A/V sync problems. It’s perfect now. If the port to the D220 Pro was configured with Auto Negotiation = Enabled and 1 GB speed it had around 1000 ms A/V sync problems and I had to plug off the power some times.