Greetings o guides to wisdom

I am starting out with Net::SNMP. I am trying to query a switch's switching table. This goes OK, except it appears that Net::SNMP is garbling a couple of the MAC addresses when processing the result of the queries.

This is the fragment of code in question: 

#!/usr/bin/perl
use strict;
use Net::SNMP qw(snmp_dispatcher oid_lex_sort);

my $host = '3c39t1-01';
my $raw;
my $key;
my $value;
my %macTable;
my $TpFdbAddress = '1.3.6.1.2.1.17.4.3.1.1';
my $result;

my ($session, $error) = Net::SNMP->session(
    -hostname  => $ARGV[0] || $host,
    -community => $ARGV[1] || 'public',
    -port      => $ARGV[2] || 161
);
if (!defined($session))
{
    printf("ERROR: %s\n", $error);
    exit 1;
}

if (defined($result = $session->get_table(-baseoid => $TpFdbAddress)))
{
    foreach (oid_lex_sort(keys(%{$result})))
    {
        $raw   = $_;
        $value = $result->{$_};
        $raw =~ s/$TpFdbAddress.//;
        $macTable{$raw} = $value;
    }
}
else
{
    printf("ERROR: %s\n\n", $session->error());
}

$session->close;

foreach $key (sort(keys(%macTable)))
{
    print "$key -> $macTable{$key}\n";
}
exit 0;

[download]
Running it results in output like this: 
[snip]
0.13.162.0.144.140 -> 0x000da200908c
0.13.86.118.96.80 -> ^@^MVv`P
0.13.86.171.103.33 -> 0x000d56ab6721
0.13.86.178.142.133 -> 0x000d56b28e85
0.13.86.225.88.22 -> 0x000d56e15816
0.13.86.32.12.60 -> ^@^MV ^L<
0.14.12.99.128.216 -> 0x000e0c6380d8
[snip]

[download]
As you can see, the "value" for a couple of the keys is garbled. These values are always garbled when the script runs, and the values are always garbled even when the same key and value results from a query on a different switch. This confuses me. When I query one of the OIDs directly which have the corrupt value, it looks OK: 
$ snmpget -v 1 -c public 3c39t1-01 1.3.6.1.2.1.17.4.3.1.1.0.13.86.32.1
+2.60
SNMPv2-SMI::mib-2.17.4.3.1.1.0.13.86.32.12.60 = Hex-STRING: 00 0D 56 2
+0 0C 3C

[download]
My first instinct is that I am doing something wrong. Can anyone see what it is?

Thank you for your time.

In reply to Net::SNMP result oddity by mackdav

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