Strangest "audio glitches" with sc_trans

[djsuck]

Hi everyone,

I'm having a problem with sc_trans (I guess) and it's really killing me.

Here is my Setup:
Server:
Core i7-4770 QuadCore
32GB RAM
2x2TB SATA 6Gb/s 7200 rpm
Guaranteed Bandwidth: 200 Mbit/s

Bare metal I installed a Citrix XenServer 6.02

The first virtual machine (where Shoutcast-Server/sc_serv and sc_trans runs on)
is a Debian 7.2 (fully updated) with 8GB of RAM.

The second VM is a Win7 with 8GB of Ram, Winamp 5.65 and the DSP-Plugin (2.3.3)

The third VM is a Sophos UTM Firewall, which is "in front" of everything.

The Win7-VM streams the audio signal to sc_trans on the Debian-machine
and connects to it as a "DJ" over Port 8505.

sc_trans is set up to relay the stream to two seperate instances of sc_serv on the same machine (192K AAC and 32K AAC).

So far everything works like a charm:
- Playlist (on the debian machine) works
- Different DJs can connect (priorities work)
- pretty much everything works

BUT:
After ~ 20-40 minutes of continuous streaming from the Win7-VM to sc_trans, "audio glitches" occur.
The sound "skips" for like a tenth of a second every couple of seconds and "blips" and "blobs" can be heard.

I spent > 50 hours troubleshooting these audio glitches, but I can't solve that problem.

Here is, what's NOT causing it:
- Hardware/Virtualisation (Had the same issues on a bare metal Debian machine)
- Firewall (The traffic from Winamp over sc_trans to sc_serv is internally without any Firewalls between)
- sc_serv (When I stream directly to sc_serv, everything is fine)
- DSP-Plugin (I tried 2.2.1, 2.3.2 & 2.3.3, also the stream written to disk sounds fine)
- OS (Same issues on two different Debian 5.0 machines)
- Encoder (I tried 192K, 128K and 96K both on mp3 and aac)
- Defective Installation (I (re-) installed the whole infrastructure 3 times)
- User (tried root and my shoutcast-User on every installation)
- Ports (Same Issues on port 8000, 8010, 8080...)
- Streaming Win7-machine (Same issues with other sources)

In my opinion, that pretty much only leaves sc_trans, right?
When the stream is faulty and I kill the sc_trans process and start it right afterwards
everything is fine... for another 20-40 minutes.

Here are my configs (URLs, PWs etc. obfuscated):

sc_trans.conf

PHP Code:

logfile=logs/sc_trans.log
calendarrewrite=0

encoder_1=aac
bitrate_1=192000
encoder_2=aac
bitrate_2=32000

outprotocol_1=3
serverip_1=127.0.0.1

outprotocol_2=3
serverip_2=127.0.0.1


serverport_1=8080
serverport_2=8000

password_1=password
password_2=password

streamid_1=1
streamid_2=1

endpointname_1=/Endpoint1
endpointname_2=/Endpoint2_64K

streamtitle=Cool title
streamurl=http://www.example.com
genre=House

adminport=7999
adminuser=admin
adminpassword=admin_password

unlockkeyname=My Name
unlockkeycode=XXXXXXXXXXXXXXXXXXXXXXXX

djport=8500
djport2=8505

djlogin_1=dj1
djpassword_1=pw1
djpriority_1=10

djlogin_2=dj2
djpassword_2=pw2
djpriority_2=5

djlogin_3=dj3
djpassword_3=pw3
djpriority_3=3

djlogin_4=dj4
djpassword_4=pw4
djpriority_4=1

calendarfile=calendar/dj_calendar.xml
playlistfile=playlists/playlist.lst 


1 of the sc_serv.conf:

PHP Code:

MaxUser=150
logfile=logs/sc_serv.log
w3clog=logs/sc_w3c.log
banfile=control/sc_serv.ban
ripfile=control/sc_serv.rip

publicserver=always
streamauthhash_1=XXXXXXXXXXXXXXXXXXXXXXXXXXXX

portbase=8080

password=password

adminpassword=admin_password

streamid=1
streampath=/streamname.mp3 


Can you guys PLEASE help me with this issue.
Has anybody experienced this kind of audio glitches an got rid of them?

Thank you so much in advance!

- Benjamin -