assertion failed in ParMETIS_V3_PartMeshKway()

Dear All,

I have a problem, when I am trying to partition mesh using Parmetis. Most cases work fine, but occasionally I got crashes like this:

[ 0] [ 7] [ 1] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[ 5] [ 9] [13] [11] [ 8] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[14] [ 7] [ 1] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[ 5] [ 2] [10] 0.0083 0.0082 0.0083
***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[12] [15] 0.0083 0.0082 0.0083
***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[ 3] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[ 2] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[10] ***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
***ASSERTION failed on line 533 of file /opt/apps/intel13/mvapich2_1_9/petsc/3.5/externalpackages/sandybridge/parmetis-4.0.2-p5/libparmetis/kwayrefine.c:ognpwgts[j*ncon+h] <= badmaxpwgt[j*ncon+h] || pgnpwgts[j*ncon+h] <= ognpwgts[j*ncon+h]
[15] [11] [ 6] [12] 0.0083 0.0082 0.0083
[ 3] 0.0083 0.0082 0.0083

The above log was generated when I was trying to partition a mesh of 1M elements into 128 partitions. The mesh is shape of cube divided into hexahedral elements.

I would be very grateful for any suggestions or hints how to deal with this problem.

Best regards,
Robert