MQTT newbie troubles

I'm publishing the same topic over and over again, using the node mqtt module on my computer, and occasionally I'm getting incomplete data printed out in Espruino. I assume the Espruino MQTT code is to blame because the client matched on the topic, yet the output doesn't match.

{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
Connection refused, unknown return code: 115.
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
MQTT unsupported packet type: 0
[MQTT]0,27,115,98,95,112,108,97,116,102,111,114,109,47,118,49,47,116,101,115,95,49,54,48,48,50,98,48,48,49,48,48
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "10", 
  "dup": 0, "qos": 0, "retain": 0 }
10
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
{ 
  "topic": "sb_platform/v1/tes_16002b00", 
  "message": "100", 
  "dup": 0, "qos": 0, "retain": 0 }
100
{ 
  "topic": "sb_plat", 
  "message": "", 
  "dup": 0, "qos": 0, "retain": 0 }

MQTT unsupported packet type: 6
[MQTT]102,111,114,109,47,118,49,47,116,101,115,95,49,54,48,48,50,98,48,48,103,111