==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.6.0
- Linux/BSD distribution name and version: Centos 5.11
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx):Apache
- Manage mail accounts with iRedAdmin-Pro?No
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

Jul 19 16:16:07 linux1 amavis[30767]: (30767-01) Passed CLEAN {RelayedOutbound}, LOCAL [???.???.???.???]:62490 [???.???.???.???] <> -> <????@????.com>, Message-ID: <??????>, mail_id: dE4GmOnnm
K7w, Hits: -, size: 3451, queued_as: 6825EA4CFB, 289585 ms

Jul 19 16:22:05 linux1 amavis[30767]: (30767-02) (!)ClamAV-clamd av-scanner FAILED: run_av error: ask_daemon_internal: Exceeded allowed time at (eval 115) line 598.\n
Jul 19 16:22:05 linux1 amavis[30767]: (30767-02) (!)WARN: all primary virus scanners failed, considering backups
Jul 19 16:22:11 linux1 amavis[30767]: (30767-02) (!)run_av (ClamAV-clamscan) FAILED - unexpected exit 2, output="WARNING: Ignoring deprecated option --disable-summary\nERROR: Option --tempdir requires a non-empty string argument\nERROR:
Can't parse command line options"
Jul 19 16:22:11 linux1 amavis[30767]: (30767-02) (!)ClamAV-clamscan av-scanner FAILED: /usr/bin/clamscan unexpected exit 2, output="WARNING: Ignoring deprecated option --disable-summary\nERROR: Option --tempdir requires a non-empty strin
g argument\nERROR: Can't parse command line options" at (eval 115) line 897.
Jul 19 16:22:12 linux1 amavis[30767]: (30767-02) (!!)AV: ALL VIRUS SCANNERS FAILED
Jul 19 16:22:25 linux1 amavis[30754]: (30754-02) (!)ClamAV-clamd av-scanner FAILED: run_av error: ask_daemon_internal: Exceeded allowed time at (eval 115) line 598.\n
Jul 19 16:22:26 linux1 amavis[30754]: (30754-02) (!)WARN: all primary virus scanners failed, considering backups
Jul 19 16:22:36 linux1 amavis[30754]: (30754-02) (!)run_av (ClamAV-clamscan) FAILED - unexpected exit 2, output="WARNING: Ignoring deprecated option --disable-summary\nERROR: Option --tempdir requires a non-empty string argument\nERROR:
Can't parse command line options"
Jul 19 16:22:36 linux1 amavis[30754]: (30754-02) (!)ClamAV-clamscan av-scanner FAILED: /usr/bin/clamscan unexpected exit 2, output="WARNING: Ignoring deprecated option --disable-summary\nERROR: Option --tempdir requires a non-empty strin
g argument\nERROR: Can't parse command line options" at (eval 115) line 897.
Jul 19 16:22:36 linux1 amavis[30754]: (30754-02) (!!)AV: ALL VIRUS SCANNERS FAILED
Jul 19 16:23:24 linux1 amavis[30754]: (30754-02) Passed UNCHECKED {RelayedOutbound}, LOCAL [???.???.???.???]:62490 [???.???.???.???] <> -> <????@????.com>, Message-ID: <??????>, mail_id: icFBI
Qb9c38X, Hits: -, size: 3455, queued_as: 25B3EA4CF9, 408740 ms
Jul 19 16:23:25 linux1 amavis[30767]: (30767-02) Passed UNCHECKED {RelayedOutbound}, LOCAL [???.???.???.???]:62511 [???.???.???.???] <> -> <????@????.com>, Message-ID: <??????>, mail_id: 5wXyQ
KFZziN5, Hits: -, size: 3449, queued_as: C9FB7A4CFB, 430687 ms

I found the inbound mail become very slow and after checking the maillog, I found some fail log about clamav after 16:22. What can I do to fix it?