USB Drive Keeps Disconnecting and Reconnecting

When connecting a USB drive to my knoppix system, I am able to mount the drive briefly before it disconnects. When I go to mount it again, I find that it has shifted from sda1 to sdb1, then to sdc1, sdd1, etc., every few seconds. Checkingvar-log-messages (below) shows that Linux thinks the device is disconnecting and reconnecting.

I don't have any trouble when I connect the USB drive to my Windows system. Any ideas what could be wrong? Any advice appreciated.

Knoppix distro, Kernel version 2.6.13.2-chw-3.

Thanks, David

Apr 1 19:25:58 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors ( 19724 MB) Apr 1 19:25:58 mythtv kernel: sdf: Write Protect is off Apr 1 19:25:58 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors ( 19724 MB) Apr 1 19:25:58 mythtv kernel: sdf: Write Protect is off Apr 1 19:25:58 mythtv kernel: sdf: sdf1 Apr 1 19:25:58 mythtv kernel: Attached scsi removable disk sdf at scsi134, chan nel 0, id 0, lun 0 Apr 1 19:25:58 mythtv kernel: Attached scsi generic sg0 at scsi134, channel 0, id 0, lun 0, type 0 Apr 1 19:25:59 mythtv scsi.agent2450: disk atdevices-pci0000:00-0000:00:02.

2-usb3-3-4-3-4:1.0-host134-target134:0:0-134:0:0:0 Apr 1 19:26:42 mythtv kernel: usb 3-4: USB disconnect, address 21 Apr 1 19:26:42 mythtv kernel: usb 3-4: new high speed USB device using ehcihcd and address 22 Apr 1 19:26:44 mythtv kernel: scsi135 : SCSI emulation for USB Mbutt Storage devices Apr 1 19:26:44 mythtv usb.agent2548: usb-storage: already loaded Apr 1 19:26:49 mythtv kernel: Vendor: Archos Model: Gmini402 Rev: 0000 Apr 1 19:26:49 mythtv kernel: Type: Direct-Access ANSI SCSI revision: 04 Apr 1 19:26:49 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:26:49 mythtv kernel: sdf: Write Protect is off Apr 1 19:26:49 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:26:49 mythtv kernel: sdf: Write Protect is off Apr 1 19:26:49 mythtv kernel: sdf: sdf1 Apr 1 19:26:49 mythtv kernel: Attached scsi removable disk sdf at scsi135, channel 0, id 0, lun 0 Apr 1 19:26:49 mythtv kernel: Attached scsi generic sg0 at scsi135, channel 0, id 0, lun 0, type 0 Apr 1 19:26:50 mythtv scsi.agent2589: disk atdevices-pci0000:00-0000:00:02.2-usb3-3-4-3-4:1.0-host135-target135:0:0-135:0:0:0 Apr 1 19:27:13 mythtv kernel: usb 3-4: USB disconnect, address 22 Apr 1 19:27:13 mythtv kernel: usb 3-4: new high speed USB device using ehcihcd and address 23 Apr 1 19:27:14 mythtv kernel: scsi136 : SCSI emulation for USB Mbutt Storage devices Apr 1 19:27:15 mythtv usb.agent2686: usb-storage: already loaded Apr 1 19:27:19 mythtv kernel: Vendor: Archos Model: Gmini402 Rev: 0000 Apr 1 19:27:19 mythtv kernel: Type: Direct-Access ANSI SCSI revision: 04 Apr 1 19:27:19 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:27:19 mythtv kernel: sdf: Write Protect is off Apr 1 19:27:19 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:27:19 mythtv kernel: sdf: Write Protect is off Apr 1 19:27:19 mythtv kernel: sdf: sdf1 Apr 1 19:27:19 mythtv kernel: Attached scsi removable disk sdf at scsi136, channel 0, id 0, lun 0 Apr 1 19:27:19 mythtv kernel: Attached scsi generic sg0 at scsi136, channel 0, id 0, lun 0, type 0 Apr 1 19:27:20 mythtv scsi.agent2727: disk atdevices-pci0000:00-0000:00:02.2-usb3-3-4-3-4:1.0-host136-target136:0:0-136:0:0:0 Apr 1 19:27:22 mythtv kernel: usb 3-4: USB disconnect, address 23 Apr 1 19:27:23 mythtv kernel: usb 3-4: new high speed USB device using ehcihcd and address 24 Apr 1 19:27:24 mythtv kernel: scsi137 : SCSI emulation for USB Mbutt Storage devices Apr 1 19:27:24 mythtv usb.agent2812: usb-storage: already loaded Apr 1 19:27:29 mythtv kernel: Vendor: Archos Model: Gmini402 Rev: 0000 Apr 1 19:27:29 mythtv kernel: Type: Direct-Access ANSI SCSI revision: 04 Apr 1 19:27:29 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:27:29 mythtv kernel: sdf: Write Protect is off Apr 1 19:27:29 mythtv kernel: SCSI device sdf: 38523870 512-byte hdwr sectors (19724 MB) Apr 1 19:27:29 mythtv kernel: sdf: Write Protect is off Apr 1 19:27:29 mythtv kernel: sdf: sdf1 Apr 1 19:27:29 mythtv kernel: Attached scsi removable disk sdf at scsi137, channel 0, id 0, lun 0 Apr 1 19:27:29 mythtv kernel: Attached scsi generic sg0 at scsi137, channel 0, id 0, lun 0, type 0 Apr 1 19:27:30 mythtv scsi.agent2854: disk atdevices-pci0000:00-0000:00:02.2-usb3-3-4-3-4:1.0-host137-target137:0:0-137:0:0:0 Apr 1 19:27:34 mythtv kernel: usb 3-4: USB disconnect, address 24 Apr 1 19:27:34 mythtv kernel: usb 3-4: new high speed USB device using ehcihcd and address 25 Apr 1 19:27:36 mythtv kernel: scsi138 : SCSI emulation for USB Mbutt Storage devices Apr 1 19:27:36 mythtv usb.agent2939: usb-storage: already loaded