OpenVox ISDN card not loading

I have found the following problem on clients that are using the 2 port and 4 port OpenVox ISDN cards. I will just like to know if you know any reason for this happening.
We reboot our Asterisk PBX system once every week and found the OpenVox is not getting detected.

Below is the list of PCI cards and drives installed on the system before we reboot the system:
[root@pbx-jhb ~]# lspci
00:00.0 Host bridge: Intel Corporation Core Processor DRAM Controller (rev 02)
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02)
00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06)
00:16.2 IDE interface: Intel Corporation 5 Series/3400 Series Chipset PT IDER Controller (rev 06)
00:16.3 Serial controller: Intel Corporation 5 Series/3400 Series Chipset KT Controller (rev 06)
00:19.0 Ethernet controller: Intel Corporation 82578DC Gigabit Network Connection (rev 06)
00:1a.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06)
00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 06)
00:1d.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev a6)
00:1f.0 ISA bridge: Intel Corporation 5 Series Chipset LPC Interface Controller (rev 06)
00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 6 port SATA AHCI Controller (rev 06)
00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 06)
01:02.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10)

As you can see the ISDN card doesn't show on this list.

Below is the list of PCI cards and drives installed after we manually reboot the PBX again:
p[root@pbx-jhb ~]# lspci
00:00.0 Host bridge: Intel Corporation Core Processor DRAM Controller (rev 02)
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02)
00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06)
00:16.2 IDE interface: Intel Corporation 5 Series/3400 Series Chipset PT IDER Controller (rev 06)
00:16.3 Serial controller: Intel Corporation 5 Series/3400 Series Chipset KT Controller (rev 06)
00:19.0 Ethernet controller: Intel Corporation 82578DC Gigabit Network Connection (rev 06)
00:1a.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06)
00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 06)
00:1d.0 USB Controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 06)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev a6)
00:1f.0 ISA bridge: Intel Corporation 5 Series Chipset LPC Interface Controller (rev 06)
00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 6 port SATA AHCI Controller (rev 06)
00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 06)
01:01.0 ISDN controller: Cologne Chip Designs GmbH ISDN network Controller [HFC-4S] (rev 01)
01:02.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10)

Hope any ones got some ideas related to this problem. It seams to be happening very intermittent on clients, however we have had clients having this problem twich this year already.

We are using Cento 5.5, Kernel 2.6.18-194.el5.

HI

Did the server have another PCI/PCI-E slot to change for the BRI card?
Please contact me by Skype or MSN,The following are the accounts :

Skype:upper.hua
MSN:[email protected]

Best regards
upper

As discussed over Skype you have requested that we change the Card to different interface port to see if it improves or if the fault still continues.

I will get this done at some of the clients to confirm if it resolves the problem.

Regards