hp laserjet professional p1606dn prints only a part content in a paper accidentally

Our products use HPLIP (version 3.9.2) to drive hp laserjet professional p1606dn to work via LAN. It works well in most cases. Unfortunately, there is some sporadic fault that it prints only a front part of content and the size of output is random. The failure rate is larger than 1%. But our products drive other printers fluently, such as p1505.
We captured the PJL CMDs sent to the printer using WireShark and found out that the data are intact. We retransmitted the captured data and the content was printed completely. Compared the normal and abnormal situation, we discovered that 2 packets were sent from the printer in normal situation and not in the abnormal situation.
Is the fault due to using the low version HPLIP? Can APDK device class “LJMono” drive p1606dn fluently? We knew that the APDK device class of p1606dn is LJZjsMono when we tried to update it to version 3.12.10. And, it needs load a “lj.so” plugin. But our products software is compiled in nucleus platform and runs in Freescale hardware. So, we need the open source of the lib. However, where can get the open source? Or, how can I drive P1606dn if I am lack of the plugin for compress? If I don’t use “lj.so” to drive P1606dn, will the quality of printed output be lower, such as above fault?

Summery:
1. Is the fault due to using the low version HPLIP?
2. Can APDK device class “LJMono” drive p1606dn fluently?
3. How can I drive P1606dn if I am lack of the plugin for compress?
4. Is there any solution for this problem?