Certain province class MCU use VP8620, the area below use VP2620 as its MCU. Two class MCU use digital cascade connection to construct the province network. When VP2620 join the conference that started by VP8620, comes out big noise and the noise won’t stop. Close the sound port that corresponding to VP2620, the noise disappeared. Open again, noise still exists.
Quite large noise
1. Check the sound protocol of conference that VP2620 started, it’s G.722. And the protocol of conference that VP8620 started is G.711A.
2. Close the conference that VP2620 started, set the conference sound protocol to G.711A and restart the conference.
3. Join the conference and there is no more noise.
Then sound has noise mainly because of the wrong peripheral setting causing sound self-excitation. The other possibility is conference TV equipment cascade connecting with different protocols causing sound coding and decoding differently, and emerge noise.