On 6224; variation in Ping response times between vlan IP, Monitor IP, and hosts

I am wondering if anyone has observed that when you ping against the management interface or hosts (attached to access ports) you get consistent ping responses (<1ms) but when you ping against IPs assigned to vlans (on the switch) you get variable responses (see example).  If so to what might this be attributed?

(Ping against attached host = XXX.XXX.102.0)  

Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128
Reply from XXX.XXX.102.0: bytes=32 time<1ms TTL=128

(Ping against vlan IP)

Reply from 10.10.10.95: bytes=32 time=1ms TTL=64

Reply from 10.10.10.95: bytes=32 time=96ms TTL=64
Reply from 10.10.10.95: bytes=32 time=36ms TTL=64
Reply from 10.10.10.95: bytes=32 time=32ms TTL=64
Reply from 10.10.10.95: bytes=32 time=83ms TTL=64
Request timed out.
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=59ms TTL=64
Request timed out.
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=9ms TTL=64
Reply from 10.10.10.95: bytes=32 time=89ms TTL=64
Reply from 10.10.10.95: bytes=32 time=68ms TTL=64
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=97ms TTL=64
Reply from 10.10.10.95: bytes=32 time=46ms TTL=64
Reply from 10.10.10.95: bytes=32 time=125ms TTL=64
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=1ms TTL=64
Reply from 10.10.10.95: bytes=32 time=69ms TTL=64

Thanks for any responses.