Quantum Spark 1570 WAN link time to time down

[DinushaDS]

Product: Quantum Spark 1570

OS : R81.10.10

Issue : 

There is a Quantum Spark 1570 Gateway, It's WAN Port to connected Point to point link (25MB) it's connected to Head office. DNS & PABX services getting from Head office. Internet also have this link.

DMZ Port to connected 1G Internet link all users internet getting from using this link. Default route created for the this link side. 

The issue is time to time these links are down after a few minutes it's getting normal. but the internet is not disconnected it's effected by Voice. 

Notifications are shown as below,

That time Internet side links are showing like this.

Routing is configured like this

Both Links were also checked with the ISP, and they said there were no any issues with the links.

Please give a solution for this one. 

[PhoneBoy]

How are the following things configured in Device > Network > Internet?

• On the Internet Connections themselves (The Internet Connection(s) > Edit > Connection Monitoring)
• In the Configure Monitoring link

Note that you may want to adjust these thresholds based on your environment.

[Chris_Atkinson]

What "Probing settings" are configured?

If DNS server ping is selected for example via which link/s are those reachable...