Hi,
Yes i have seen the exact same thing, i have a case ongoing at HP for the last 3months with no resolve.
And its not just high ping times, the reason for high ping times is CPU load, the CPU load hits 70-80% during these high ping times.
Downgrading to WB.15.16.0012m will solve the problem for you, this is the last firmware with no issues, going to any newer ones like WB.15.18.xxx or newer introduces the problem.
I suggest you also setup a case with HP to have them resolve this!