Media monitor not works after update Airtime 2.0.3 to 2.1.2

I have just updated Airtime 2.0.3 to  2.1.2 on dedian server, but I have some errors.  

Media monitor is not working. Here is the display of airtime-check-system

AIRTIME_STATUS_URL             = http://localhost:80/api/status/format/json/api_key/%%api_key%%
AIRTIME_SERVER_RESPONDING      = OK
KERNEL_VERSION                 = 2.6.32-5-amd64
MACHINE_ARCHITECTURE           = x86_64
TOTAL_MEMORY_MBYTES            = 2027756
TOTAL_SWAP_MBYTES              = UNKNOWN
AIRTIME_VERSION                = 2.1.2
OS                             = Debian GNU/Linux 6.0.5 (squeeze) x86_64
CPU                            = VIA Nano processor U2250 (1.6GHz Capable)
WEB_SERVER                     = Apache/2.2.16 (Debian)
PLAYOUT_ENGINE_PROCESS_ID      = 9930
PLAYOUT_ENGINE_RUNNING_SECONDS = 266215
PLAYOUT_ENGINE_MEM_PERC        = 0.7%
PLAYOUT_ENGINE_CPU_PERC        = 0.0%
LIQUIDSOAP_PROCESS_ID          = 9934
LIQUIDSOAP_RUNNING_SECONDS     = 266215
LIQUIDSOAP_MEM_PERC            = 1.0%
LIQUIDSOAP_CPU_PERC            = 100.0%
MEDIA_MONITOR_PROCESS_ID       = FAILED
MEDIA_MONITOR_RUNNING_SECONDS  = -1
MEDIA_MONITOR_MEM_PERC         = 0%
MEDIA_MONITOR_CPU_PERC         = 0%
RABBITMQ_PROCESS_ID            = 1097
RABBITMQ_RUNNING_SECONDS       = 298437
RABBITMQ_MEM_PERC              = 1.3%
RABBITMQ_CPU_PERC              = 0.0%

-- There appears to be a problem with your Airtime installation.


Version : 2.6.32-5-amd64 #1 SMP Sun May 6 04:00:17 UTC 2012 x86_64 GNU/Linux


Thanks in advance
DS