Recipient address rejected: Relay access denied. How do I fix this?

Output of tail -f /var/log/maillog:
 
Mar 29 18:15:53 ip-72-167-163-127 postfix/smtpd[11644]: warning: smtpd_sasl_auth_enable is true, but SASL support is not compiled in
Mar 29 18:15:53 ip-72-167-163-127 postfix/smtpd[11644]: connect from 216-164-169-108.c3-0.tlg-ubr4.atw-tlg.pa.cable.rcn.com[216.164.169.108]
Mar 29 18:15:53 ip-72-167-163-127 postfix/smtpd[11644]: setting up TLS connection from 216-164-169-108.c3-0.tlg-ubr4.atw-tlg.pa.cable.rcn.com[216.164.169.108]
Mar 29 18:15:55 ip-72-167-163-127 postfix/smtpd[11644]: Anonymous TLS connection established from 216-164-169-108.c3-0.tlg-ubr4.atw-tlg.pa.cable.rcn.com[216.164.169.108]: TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)
Mar 29 18:15:55 ip-72-167-163-127 postfix/smtpd[11644]: warning: support for restriction "check_relay_domains" will be removed from Postfix; use "reject_unauth_destination" instead
Mar 29 18:15:55 ip-72-167-163-127 postfix/smtpd[11644]: NOQUEUE: reject: RCPT from 216-164-169-108.c3-0.tlg-ubr4.atw-tlg.pa.cable.rcn.com[216.164.169.108]: 554 5.7.1 <[email address]>: Recipient address rejected: Relay access denied; from=<[email address]> to=<[email address]> proto=ESMTP helo=<[127.0.0.1]>
Mar 29 18:15:57 ip-72-167-163-127 postfix/smtpd[11644]: disconnect from 216-164-169-108.c3-0.tlg-ubr4.atw-tlg.pa.cable.rcn.com[216.164.169.108]
 
 
main.cf
 
command_directory = /usr/sbin
daemon_directory = /usr/libexec/postfix
unknown_local_recipient_reject_code = 550
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
debug_peer_level = 2
 
debugger_command =
         PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
         xxgdb $daemon_directory/$process_name $process_id & sleep 5
 
sendmail_path = /usr/sbin/sendmail.postfix
newaliases_path = /usr/bin/newaliases.postfix
mailq_path = /usr/bin/mailq.postfix
setgid_group = postdrop
html_directory = no
manpage_directory = /usr/share/man
sample_directory = /usr/share/doc/postfix-2.3.6/samples
readme_directory = /usr/share/doc/postfix-2.3.6/README_FILES
smtpd_sasl_local_domain = 
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions = permit_mynetworks permit_inet_interfaces permit_sasl_authenticated check_relay_domains
smtpd_tls_auth_only = no
smtp_use_tls = yes
smtp_tls_note_starttls_offer = yes
smtpd_tls_key_file = /etc/postfix/ssl/smtpd.key
smtpd_tls_cert_file = /etc/postfix/ssl/smtpd.crt
smtpd_tls_CAfile = /etc/postfix/ssl/cacert.pem
smtpd_tls_loglevel = 1
smtpd_tls_received_header = yes
smtpd_tls_session_cache_timeout = 3600s
tls_random_source = dev:/dev/urandom
smtpd_sasl_authenticated_header = yes
relayhost = k2smtpout.secureserver.net
myorigin = $mydomain
smtpd_use_tls = yes
smtpd_sasl_auth_enable = yes
 
 
master.cf
 
# ==========================================================================
# service type  private unpriv  chroot  wakeup  maxproc command + args
#               (yes)   (yes)   (yes)   (never) (100)
# ==========================================================================
smtp      inet  n       -       -       -       -       smtpd -o content_filter=spamassassin
pickup    fifo  n       -       n       60      1       pickup
cleanup   unix  n       -       n       -       0       cleanup
qmgr      fifo  n       -       n       300     1       nqmgr
rewrite   unix  -       -       n       -       -       trivial-rewrite
bounce    unix  -       -       n       -       0       bounce
defer     unix  -       -       n       -       0       bounce
flush     unix  n       -       n       1000?   0       flush
proxymap  unix  -       -       n       -       -       proxymap
smtp      unix  -       -       n       -       -       smtp
relay     unix  -       -       n       -       -       smtp
showq     unix  n       -       n       -       -       showq
error     unix  -       -       n       -       -       error
local     unix  -       n       n       -       -       local
virtual   unix  -       n       n       -       -       virtual
lmtp      unix  -       -       n       -       -       lmtp
maildrop  unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail argv=/usr/local/bin/maildrop -d ${recipient}
old-cyrus unix  -       n       n       -       -       pipe
  flags=R user=cyrus argv=/cyrus/bin/deliver -e -m ${extension} ${user}
cyrus     unix  -       n       n       -       -       pipe
  user=cyrus argv=/cyrus/bin/deliver -e -r ${sender} -m ${extension} ${user}
uucp      unix  -       n       n       -       -       pipe
  flags=Fqhu user=uucp argv=uux -r -n -z -a$sender - $nexthop!rmail ($recipient)
ifmail    unix  -       n       n       -       -       pipe
  flags=F user=ftn argv=/usr/lib/ifmail/ifmail -r $nexthop ($recipient)
bsmtp     unix  -       n       n       -       -       pipe
  flags=Fq. user=foo argv=/usr/local/sbin/bsmtp -f $sender $nexthop $recipient
spamassassin
          unix  -       n       n       -       -       pipe
  user=nobody argv=/usr/bin/spamc -f
                   -e /usr/sbin/sendmail.postfix 
                   -oi -f ${sender} ${recipient}
trace     unix  -       -       n       -       0       bounce
verify    unix  -       -       n       -       1       verify
anvil     unix  -       -       n       -       1       anvil
scache    unix  -       -       n       -       1       scache
discard   unix  -       -       n       -       -       discard
tlsmgr    unix  -       -       n       1000?   1       tlsmgr
retry     unix  -       -       n       -       -       error
proxywrite unix -       -       n       -       1       proxymap
                                  

1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:
80:
81:
82:
83:
84:
85:
86:
87:
88:
89:
90:
91:
92:
93:
94:
95:
96:
97:
98:
99: