请问下大家，2960接入交换机办公用（出厂默认配置，相当于hub），不同端口会闪断，断了一会又好了，可能是什么问题，2960也换过了。
Log Buffer (4096 bytes):
5-UPDOWN: Line protocol on Interface FastEthernet0/16, changed state to up
*Mar 12 21:07:33.416: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/31, changed state to down
*Mar 12 21:07:35.387: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/16, changed state to down
*Mar 12 21:07:35.438: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/31, changed state to up
*Mar 12 21:07:37.409: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/16, changed state to up
*Mar 12 21:09:51.434: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/40, changed state to down
*Mar 12 21:09:53.439: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/40, changed state to up
*Mar 12 21:10:11.365: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/35, changed state to down
*Mar 12 21:10:13.370: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/35, changed state to up
*Mar 12 21:14:54.716: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/44, changed state to down
*Mar 12 21:14:56.720: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/44, changed state to up
*Mar 12 21:15:09.832: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/44, changed state to down
*Mar 12 21:15:11.845: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/44, changed state to up
*Mar 12 21:25:45.554: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/41, changed state to down
*Mar 12 21:25:47.559: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/41, changed state to up
