最近几天有几颗AP老是频繁掉线，ap型号为2702 ，掉线的日志如下，哪位大神给解答一下，谢谢！*spamApTask6: Mar 26 08:00:26.012: %LWAPP-3-VENDOR_PLD_VALIDATE_ERR: spam_lrad.c:11970 Validation of SPAM_VENDOR_SPECIFIC_PAYLOAD(185) with length=9 failed - AP 70:70:8b:d7:be:d0

WLC 5508升级失败，目前是8.0.120版本，升级8.3失败，请哪位大神指导一下？