TF2 Server subject to crashing, help!

[CharmQuark]

Server OS: The server is externally hosted, so I'm unsure.
Processor: As above.
Ram: As above.
Game(s): Team Fortress 2
Start Up Command: -game tf -console +fps_max 66 +ip 119.252.191.69 -port 27145 +maxplayers 16 +exec server.cfg +map "arena_lumberyard" -condebug -replay
Admin Mods: SourceMod, MetaMod.

NETWORK AND BANDWIDTH INFO
Bandwidth: Again, I'm unsure.
Router: As above.
Local IP of Server: Unsure.
External IP: 119.252.191.69:27145.
Port Forwarding Screen Shot: ? Nope.

CONFIG ISSUES
// Arena Settings
tf_arena_use_queue 0
maxplayers 16
mapcyclefile "arena_mapcycle.txt"
tf_weapon_criticals 0
tf2items_rnd_betaweapons 0
tf2items_rnd_customweapons 0
sv_tags arena,australia,randomizer,melee,stats,no queue

hostname ** The Love Emporium | r/tf2au | **
sv_visiblemaxplayers 16
host_framerate 0
setpause 0
sv_pure 1
sv_pausable 0
sv_lan 0
sv_consistency 1
sv_stats 1
exec banned_user.cfg
exec banned_ip.cfg
writeid
writeip
sv_region 5
sv_rcon_banpenalty 1440
sv_rcon_maxfailures 5
log on
sv_log_onefile 0
sv_logfile 1
sv_logbans 1
sv_logecho 1

fps_max 100
sv_minrate 30000
sv_maxrate 50000
sv_minupdaterate 33
sv_maxupdaterate 66
sv_mincmdrate 33
sv_maxcmdrate 66


sv_allowupload 1
sv_allowdownload 1
net_maxfilesize 15
mp_autoteambalance 1
mp_autoteambalance_delay 60
mp_autoteambalance_warning_delay 30
mp_teams_unbalance_limit 1
mp_enableroundwaittime 1
mp_bonusroundtime 8
mp_restartround 0
mp_stalemate_enable 1
mp_stalemate_timelimit 300
mp_timelimit 20
mp_forcecamera 0
mp_allowspectators 1
mp_footsteps 1
sv_cheats 0
sv_timeout 900
mp_idlemaxtime 15
mp_idledealmethod 2
decalfrequency 30
sv_voiceenable 1
sv_alltalk 0
mp_chattime 10
// enable party mode
// tf_birthday 1

(this is in the arena config, in the server cfg I have ...)
exec config_arena
exec replay.cfg
tf_server_identity_account_id 49224
tf_server_identity_token "hekmQ&Lbkp!O-hV"

The server keeps randomly crashing when only 8 or so players are even on it! The last crash the log file recorded:

L 04/13/2012 - 19:31:16: Connection to Steam servers lost. (Result = 3)
L 04/13/2012 - 19:31:18: "Tyrannicide<89><STEAM_0:0:40187998><Blue>" killed "-|BM|- InVeRsIoN<88><STEAM_0:0:25615185><Red>" with "world" (attacker_position "561 -99 56") (victim_position "1067 -937 81")
L 04/13/2012 - 19:31:18: World triggered "Round_Win" (winner "Blue")
L 04/13/2012 - 19:31:18: World triggered "Round_Length" (seconds "72.72")
L 04/13/2012 - 19:31:18: Team "Red" current score "4" with "2" players
L 04/13/2012 - 19:31:18: Team "Blue" current score "6" with "3" players
L 04/13/2012 - 19:31:26: World triggered "Round_Start"
L 04/13/2012 - 19:31:53: "Tyrannicide<89><STEAM_0:0:40187998><Blue>" killed "-|BM|- InVeRsIoN<88><STEAM_0:0:25615185><Red>" with "sniperrifle" (customkill "headshot") (attacker_position "1720 1696 352") (victim_position "1711 618 70")
L 04/13/2012 - 19:31:53: "Tyrannicide<89><STEAM_0:0:40187998><Blue>" triggered "domination" against "-|BM|- InVeRsIoN<88><STEAM_0:0:25615185><Red>"
L 04/13/2012 - 19:32:06:
********************************************************************************​
*
L 04/13/2012 - 19:32:06: *
*
* ** ERROR: Couldn't connect to server
*
L 04/13/2012 - 19:32:06: *
********************************************************************************​

L 04/13/2012 - 19:32:07:
********************************************************************************​
*
L 04/13/2012 - 19:32:07: * Replay recording shutting down due to publishing error! Recording will begin
L 04/13/2012 - 19:32:07: * at the beginning of the next round, but may fail again.
L 04/13/2012 - 19:32:07: *
********************************************************************************​

L 04/13/2012 - 19:32:47: "-|BM|- InVeRsIoN<88><STEAM_0:0:25615185><Red>" say "are you guys getting mad bad lag ?"
L 04/13/2012 - 19:32:47: Connection to Steam servers successful.
L 04/13/2012 - 19:32:47: Public IP is 119.252.191.100.
L 04/13/2012 - 19:32:47: Assigned anonymous gameserver Steam ID [A-1:2413706242(2929)].
L 04/13/2012 - 19:32:47: VAC secure mode is activated.
L 04/13/2012 - 19:32:47: STEAMAUTH: Client -|BM|- InVeRsIoN received failure code 6
L 04/13/2012 - 19:32:47: "-|BM|- InVeRsIoN<88><STEAM_0:0:25615185><Red>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: STEAMAUTH: Client Tyrannicide received failure code 6
L 04/13/2012 - 19:32:47: "Tyrannicide<89><STEAM_0:0:40187998><Blue>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: STEAMAUTH: Client ╚(:3)╗ Otter received failure code 6
L 04/13/2012 - 19:32:47: "╚(:3)╗ Otter<93><STEAM_0:0:25010598><Blue>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: STEAMAUTH: Client but smuggler received failure code 6
L 04/13/2012 - 19:32:47: "but smuggler<99><STEAM_0:0:23356445><Unassigned>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: STEAMAUTH: Client Gold Ghost received failure code 6
L 04/13/2012 - 19:32:47: "Gold Ghost<102><STEAM_0:1:45248182><Red>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: STEAMAUTH: Client Squadallah received failure code 6
L 04/13/2012 - 19:32:47: "Squadallah<105><STEAM_0:0:45724254><Blue>" disconnected (reason "Client left game (Steam auth ticket has been canceled)
")
L 04/13/2012 - 19:32:47: tf_server_identity_account_id not set; not logging into registered account
L 04/13/2012 - 19:32:47: World triggered "Round_Stalemate"
L 04/13/2012 - 19:32:47: Team "Red" current score "4" with "0" players
L 04/13/2012 - 19:32:47: Team "Blue" current score "6" with "0" players
L 04/13/2012 - 19:32:55: World triggered "Round_Start"
L 04/13/2012 - 19:33:03: "UkKeE_PrimE<106><STEAM_0:1:46429933><>" entered the game

Is this my hosts problem? i.e. bandwidth issue? Is there anything I can do to fix it myself?