增加断网超时说明

Signed-off-by: Nz00502384 <zhangyue117@huawei.com>
Change-Id: Ic4122ee6f81cc8f4294d62e904109ecc70bf790c

en/application-dev/reference/errorcodes/errorcode-media.md

@@ -71,7 +71,7 @@ The operation timed out.
 
 **Possible Causes**
 
-1. The network connection times out.
+1. The network connection times out. Default timeout value is 15 seconds, starting from the reporting of buffering start event, and the error message will be reported after timeout.
 2. Accessing other modules times out.
 
 **Solution**

zh-cn/application-dev/reference/errorcodes/errorcode-media.md

@@ -71,7 +71,7 @@ Operation timeout.
 
 **可能原因**
 
-1. 网络超时。
+1. 网络超时。默认网络超时时间为15秒，从开始缓存的事件上报后开始计时，超时后会上报该错误信息。
 2. 访问其他模块超时。
 
 **处理步骤**