Stuttering sound, Cinnamon Mint 17.3, Dell Dimension T3500

Question

This overpowered six core Xeon, 12GB ECC machine with Cinnamon Mint 17.3 installed on two 7200 rpm Barracudas (160GB and 1TB), suffers from s-s-s-severe stuttering sound playback. Chipset: Intel X58+ ICH10. RAM: 12GB ECC. Per spec sheet, onboard audio is ADI1984A integrated audio

Need PulseAudio for Skype support, since M$ does not support ALSA now as per http://blogs.skype.com/2014/06/18/skype-4-3-for-linux/. Skype 4.3 is a deal breaker app.

There is no BIOS setting for AC97 or HD audio, nothing but integrated sound on or off. However, adding a Diamond Multimedia sound card (which lspci read as 06:05.0 Multimedia audio controller: C-Media Electronics Inc CMI8738/CMI8768 PCI Audio (rev 10) ), disabling the integrated audio then rebooting did not solve the stutter. Sound from the new card works, but still stutters.

Tried selecting stereo, Surround 4.0 Output, Surround 4.1 Output, Surround 5.0 Output, Surround 5.1 Output, all to no avail.

Removed card, reenable onboard audio, back to stereo.

Tried

sudo killall pulseaudio && sudo pulseaudio --system=1 --daemonize

then reboot, retry. No joy,

Added a second 7200 rpm Barracuda drive and moved the swap off the OS drive /dev/sda5 onto the new drive /dev/sdb2 (Was going to do that anyway). Confirmed it is working OK, added it to /etc/fstab, reboots OK. Sound still stutters.

What should I do next to solve this sound issue?

lspci reports:

00:00.0 Host bridge: Intel Corporation 5520/5500/X58 I/O Hub to ESI Port (rev 22)

00:01.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 1 (rev 22)

00:03.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 3 (rev 22)

00:07.0 PCI bridge: Intel Corporation 5520/5500/X58 I/O Hub PCI Express Root Port 7 (rev 22)

00:14.0 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub System Management Registers (rev 22)

00:14.1 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub GPIO and Scratch Pad Registers (rev 22)

00:14.2 PIC: Intel Corporation 7500/5520/5500/X58 I/O Hub Control Status and RAS Registers (rev 22)

00:1a.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #4

00:1a.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #5

00:1a.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #6

00:1a.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #2

00:1b.0 Audio device: Intel Corporation 82801JI (ICH10 Family) HD Audio Controller

00:1c.0 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 1

00:1c.5 PCI bridge: Intel Corporation 82801JI (ICH10 Family) PCI Express Root Port 6

00:1d.0 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #1

00:1d.1 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #2

00:1d.2 USB controller: Intel Corporation 82801JI (ICH10 Family) USB UHCI Controller #3

00:1d.7 USB controller: Intel Corporation 82801JI (ICH10 Family) USB2 EHCI Controller #1

00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 90)

00:1f.0 ISA bridge: Intel Corporation 82801JIR (ICH10R) LPC Interface Controller

00:1f.2 SATA controller: Intel Corporation 82801JI (ICH10 Family) SATA AHCI Controller

00:1f.3 SMBus: Intel Corporation 82801JI (ICH10 Family) SMBus Controller

02:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Seymour [Radeon HD 6400M/7400M Series]

02:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Caicos HDMI Audio [Radeon HD 6400 Series]

05:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5761 Gigabit Ethernet PCIe (rev 10)

3f:00.0 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture Generic Non-core Registers (rev 02)

3f:00.1 Host bridge: Intel Corporation Xeon 5600 Series QuickPath Architecture System Address Decoder (rev 02)

3f:02.0 Host bridge: Intel Corporation Xeon 5600 Series QPI Link 0 (rev 02)

3f:02.1 Host bridge: Intel Corporation Xeon 5600 Series QPI Physical 0 (rev 02)

3f:02.2 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 0 (rev 02)

3f:02.3 Host bridge: Intel Corporation Xeon 5600 Series Mirror Port Link 1 (rev 02)

3f:03.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Registers (rev 02)

3f:03.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Target Address Decoder (rev 02)

3f:03.4 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Test Registers (rev 02)

3f:04.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Control (rev 02)

3f:04.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Address (rev 02)

3f:04.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Rank (rev 02)

3f:04.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 0 Thermal Control (rev 02)

3f:05.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Control (rev 02)

3f:05.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Address (rev 02)

3f:05.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Rank (rev 02)

3f:05.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 1 Thermal Control (rev 02)

3f:06.0 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Control (rev 02)

3f:06.1 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Address (rev 02)

3f:06.2 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Rank (rev 02)

3f:06.3 Host bridge: Intel Corporation Xeon 5600 Series Integrated Memory Controller Channel 2 Thermal Control (rev 02)