setup failed -5 with garbage message

[jemiar]

I followed the instruction to connect the Yun to the AWS IoT.
My yun baud rate is 250000, but I keep the Serial.begin(115200)
When I ran the the PubSub sample, I got these in the console:

AWS IoT SDK Version(dev) 2.2.0-



switching to jffs2

- init -


ell (ash)
__
one):/# 1
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YA⸮(v]l]�
y%⸮�⸮�⸮%"mV⸮.&⸮⸮6⸮M⸮?v~hN�!⸮j⸮J�⸮�⸮%Bn⸮/]~h.X]⸮� ⸮*⸮J�⸮S⸮%���⸮nM7
�HV�m4l⸮⸮?��-~⸮~�M⸮.�GlH⸮y!⸮X�⸮-�ha⸮J�N⸮[a���⸮JHL�L
⸮[⸮
K⸮��(
Setup failed!
-5

When I change the Serial.begin(250000), I got this:

AWS IoT SDK Version(dev) 2.2.0-

- regular preinit -
  9.330000] JFFS2 notice: (537) jffs2_build_xattr_subsystem:1
[   10.500000] sd 0:0:0:0: [sda] 3891200 512-byte logical block sd 0:0:0:0
sda] No Caching mode page present
[   10.510000] sd 0:0:0:0: [sda] No Caching mode page presenive

[   10.580000]  sda: sda1


switching to jffs2
]8⸮
�>)@?AoH�vC\⸮⸮y�⸮⸮�q��LK⸮5⸮⸮X%⸮{b�⸮�LX⸮M⸮|⸮ms





Y⸮J(6]l]�
Y⸮J��⸮-⸮VV⸮.&x]⸮n⸮��^HNl�⸮Y⸮JX�⸮-⸮-J}l^H�x]o:,�1⸮J⸮��⸮-�⸮p_A/nMw
|�fv⸮��m~⸮^�-⸮��GlH⸮Y⸮JX/⸮-��!⸮J��⸮[A���⸮J�L�L3	A�<�L
Setup failed!
-5

Can you help me with this issue?
Thanks,