Devices with full path RTT sometimes have packet parsing errors

[jkilpatr]

About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < 4
About to enter subtlv parsting loop if 0 < -2
About to enter subtlv parsting loop if 0 < -2
About to enter subtlv parsting loop if 0 < -2
About to enter subtlv parsting loop if 0 < -2
About to enter subtlv parsting loop if 0 < -2
Couldn't parse packet (13, 23) from fe80::8eae:4cff:fef4:2201 on eth1.
Couldn't parse packet (13, 23) from fe80::8eae:4cff:fef4:2201 on eth1.
Couldn't parse packet (13, 31) from fe80::8eae:4cff:fef4:2201 on eth1.
Couldn't parse packet (13, 22) from fe80::8eae:4cff:fef4:2201 on eth1.
Couldn't parse packet (13, 22) from fe80::8eae:4cff:fef4:2201 on eth1.

Everything seems to work but I'm still concerned by these messages and potentially hard to find errors.