F5 VIP responding intermittently.

Folks,

We have an F5 VIP which has started to respond intermittently since the past few days. The issue here is that both the application and ICMP have intermittent response and at times no response.

What I understand is that with ICMP the F5 provides the response and not any of the backend servers, please correct me here.

Can anyone provide any initial comments on this issue?

Thanks!!

Neel.