Serial tests failing on new Pi

[stevieb9]

New test Pi:

pi@pi-test:~/repos/rpi-wiringpi $ perl t/75-serial.t 
ok 1 - An object of class 'RPi::Serial' isa 'RPi::Serial'
ok 2 - putc() and getc() ok
not ok 3 - puts() and gets() ok
#   Failed test 'puts() and gets() ok'
#   at t/75-serial.t line 27.
#          got: 'hello, world!'
#     expected: 'hello, world!'
ok 4
1..4
# Looks like you failed 1 test of 4.

Happens the vast majority of the time. Only once in a while does it pass.