Ex2200 lacp flap

Hello,

I have a ex2200 and now version is 12.3R6.6, there's some lacp flapping suddenly happened during 1 mins yesterday, there's no something interresting in logs except LACP timeout

Dec 11 19:17:40 XXXX chassism[1214]: JTASK_SCHED_SLIP_KEVENT: 21 sec 494516 usec kevent block
Dec 11 19:17:40 XXXX sfid[1215]: JTASK_SCHED_SLIP_KEVENT: 21 sec 495211 usec kevent block
Dec 11 19:17:40 XXXX eswd[1225]: JTASK_SCHED_SLIP_KEVENT: 21 sec 571357 usec kevent block
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/44 - ATTACHED state - acting as standby link
Dec 11 19:17:40 XXXX lacpd[1245]: LACPD_TIMEOUT: ge-0/0/44: lacp current while timer expired current Receive State: CURRENT
Dec 11 19:17:40 XXXX rpd[1235]: RPD_SCHED_SLIP_KEVENT: 22 sec 349263 usec kevent block
Dec 11 19:17:40 XXXX sflowd[1250]: JTASK_SCHED_SLIP_KEVENT: 25 sec 380936 usec kevent block
Dec 11 19:17:40 XXXX mcsnoopd[1251]: JTASK_SCHED_SLIP_KEVENT: 21 sec 814462 usec kevent block
Dec 11 19:17:40 XXXX cfmd[1231]: JTASK_SCHED_SLIP_KEVENT: 21 sec 905300 usec kevent block
Dec 11 19:17:40 XXXX lacpd[1245]: LACPD_TIMEOUT: ge-0/0/45: lacp current while timer expired current Receive State: CURRENT
Dec 11 19:17:40 XXXX lacpd[1245]: LACP_INTF_DOWN: ae0: Interface marked down due to lacp timeout on member ge-0/0/45
Dec 11 19:17:40 XXXX /kernel: ae_bundlestate_ifd_change: bundle ae0: bundle IFD minimum links not met 0 < 1
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/45 - ATTACHED state - acting as standby link
Dec 11 19:17:40 XXXX lacpd[1245]: LACPD_TIMEOUT: ge-0/0/47: lacp current while timer expired current Receive State: CURRENT
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/47 - ATTACHED state - acting as standby link
Dec 11 19:17:40 XXXX /kernel: ae_bundlestate_ifd_change: bundle ae1: bundle IFD minimum links not met 0 < 1
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/46 - ATTACHED state - acting as standby link
Dec 11 19:17:40 XXXX lacpd[1245]: LACPD_TIMEOUT: ge-0/0/46: lacp current while timer expired current Receive State: CURRENT
Dec 11 19:17:40 XXXX lacpd[1245]: LACP_INTF_DOWN: ae1: Interface marked down due to lacp timeout on member ge-0/0/46
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/44 - CD state - ready to carry traffic
Dec 11 19:17:40 XXXX vccpd[1216]: JTASK_SCHED_SLIP_KEVENT: 24 sec 561307 usec kevent block
Dec 11 19:17:40 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/45 - CD state - ready to carry traffic
Dec 11 19:17:41 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/47 - CD state - ready to carry traffic
Dec 11 19:17:41 XXXX /kernel: KERN_LACP_INTF_STATE_CHANGE: lacp_update_state_userspace: cifd ge-0/0/46 - CD state - ready to carry traffic
Dec 11 19:17:41 XXXX mib2d[1234]: SNMP_TRAP_LINK_DOWN: ifIndex 600, ifAdminStatus up(1), ifOperStatus down(2), ifName ae0
Dec 11 19:17:41 XXXX mib2d[1234]: SNMP_TRAP_LINK_DOWN: ifIndex 602, ifAdminStatus up(1), ifOperStatus down(2), ifName ae1

I have check RE and looks all normal, below is some information

show chassis routing-engine
Routing Engine status:
Slot 0:
Current state Master
Temperature 31 degrees C / 87 degrees F
CPU temperature 31 degrees C / 87 degrees F
DRAM 512
Memory utilization 54 percent
CPU utilization:
User 7 percent
Background 0 percent
Kernel 6 percent
Interrupt 0 percent
Idle 87 percent
Model EX2200-48T-4G
Serial ID CU0215070169
Start time 2014-03-13 17:48:10 CST
Uptime 375 days, 14 hours, 3 minutes, 58 seconds
Last reboot reason 0x1ower cycle/failure
Load averages: 1 minute 5 minute 15 minute
0.18 0.24 0.23

show virtual-chassis

How can i debug this issue?  many thanks!