QNX 6.5 on a TI DM3730 based board (basically a BeagleBoard).

Used this script per your suggestion:

echo This node is `uname -n`
for f in `ls /net`
do
  echo $f
  on -f /net/$f top -i 1
done

I get the same behavior:

# node-loads.sh
This node is e2rb_004
e2rb_001
Computing times...
19 processes; 66 threads;
CPU states: 99.5% idle, 0.2% user, 0.1% kernel
Memory: 0 total, 89M avail, page size 4K

      PID   TID PRI STATE    HH:MM:SS    CPU  COMMAND
    53258     5  21 Rcv       0:19:33   0.19% io-usb
        1     7  10 Run       0:00:04   0.19% kernel
   647186     1  10 Rply      0:00:00   0.09% top
    53258     2  21 Rcv       0:46:31   0.00% io-usb
    90125     2  21 Rcv       0:00:57   0.00% io-pkt-v4
    57355     3  10 NSlp      0:00:05   0.00% random
        1    11  21 Rcv       0:00:04   0.00% kernel
    90125     3  21 Rply      0:00:00   0.00% io-pkt-v4
    90125     4  10 Rcv       0:00:00   0.00% io-pkt-v4
   110606     1  10 NSlp      0:00:00   0.00% dhcp.client

             Min        Max       Average
CPU idle:     99%        99%        99%
Mem Avail:    89MB       89MB       89MB
Processes:    19         19         19
Threads:      66         66         66

e2rb_003
Computing times...