Symptom:
The test sends 2 pkts of size 100B, the first one is converted from 132B to 120B and RTL and REF match.
The 2nd pkt coming back from RTL has size of 124B instead of 120B.
The ebb received for this pkt is 0x3c instead of 0x38.
The converted CB hdr match but the payload does not match.

@      68.701 ns: [MSG] [vir_fg_ref_t::check] PKT 0 Data match
@      72.703 ns: [ERROR] [vir_fg_ref_t::check] PKT 1 Data size mismatch, RTL pkt.size = 124 B, REF pkt.size = 120 B
rtl size = 124 B, ref size = 120
           Byte        RTL        REF

              0 72          72
              1 01          01
              2 93          93
              3 77          77
              4 63          63
              5 84          84
              6 d0          d0
              7 b3          b3
              8 05          05
              9 ea          ea
             10 50          50
             11 00          00
             12 e0          e0
             13 0d          0d
             14 c6          c6
             15 d2          d2
             16 cc          cc
             17 73          73
             18 47          47
             19 99          99
             20 06          f3  Mismatch
             21 31          48  Mismatch
             22 f9          a9  Mismatch
             23 d4          ad  Mismatch
             24 f3          31  Mismatch
             25 48          53  Mismatch
             26 a9          40  Mismatch
             27 ad          c9  Mismatch
             28 31          cb  Mismatch
.......................................

Waveform at
/auto/nvbu-asic20/users/icozzani/voq/2014_05_05/andiamo_vegas/ip_waverider/sim/fg/fg_dc3_cb_conv/runs/test_basic_conv_194813913

Run from andiamo_vegas/ip_waverider/sim/fg/fg_dc3_cb_conv
with
runfg  -tn test_basic_conv -seed 194813913 -- +num_pkt=2

Conditions:
Run from andiamo_vegas/ip_waverider/sim/fg/fg_dc3_cb_conv
with
runfg  -tn test_basic_conv -seed 194813913 -uq -vo "+num_pkt=2 +dbg_ref=1" -dump