Hi Ioan,
The keywords are your addition to the Subject Line: "Fix the Issue."
Unfortunately, the way chip components are solder-attached to PCBs harks back 
to the requirements for wave soldering—you need large PCB soldering pads that 
can be touched by the liquid solder wave for heat and material transfer. The 
consequence of this are large solder fillets and very thin solder joint gaps 
between the CC and the PCB. The large solder fillets act like the jaws of a 
vice both during cooling from the soldering process and during any kind of PCB 
flexure, thus putting the CCs under a lot of stress; the thin solder gaps 
provide no compliance for the solder attachment, thus reducing the capability of the 
SJs to absorb some of the deflection/warpage deformation as well as thermal 
cyclic loads. The large fillet/thin SJ gap geometry is about as bad an 
attachment scenario as you can imagine.
This is explained in more detail in my Reliability Column in Global SMT & 
Packaging magazine,   “Lead-Free (LF) Wave-Soldering: Can (Should) It Be 
Eliminated,” Global SMT & Packaging, Vol. 5, No. 9, October 2005, pp. 46-50. 
As I pointed out in my column, the solder attachment geometry can be 
dramatically improved if one uses reflow rather than wave soldering. This not only 
essentially eliminates CC cracking, but has a number of other advantages as well, 
particularly with lead-free soldering. The soldering pads need to be only the 
size of the termination, eliminating the fillets and increasing the SJ gap 
between CC and PCB.

Werner

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