SanDisk sansa worked ok (i.e. could be mounted as a filesystem) until quite recently.
XXXX:~$ uname -a
Linux XXXX 4.15.0-58-generic #64-Ubuntu SMP Tue Aug 6 11:12:41 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
XXXX:~$ lsusb
Bus 001 Device 009: ID 0781:7430 SanDisk Corp. Sansa M200 series
XXXX:~$ tail -n NNN /var/log/syslog
Aug 26 20:50:26 XXXX kernel: [37413.780115] usb 1-1.3: new high-speed USB device number 9 using ehci-pci
Aug 26 20:50:26 XXXX kernel: [37413.896471] usb 1-1.3: New USB device found, idVendor=0781, idProduct=7430
Aug 26 20:50:26 XXXX kernel: [37413.896474] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Aug 26 20:50:26 XXXX kernel: [37413.896475] usb 1-1.3: Product: SanDisk Sansa m240
Aug 26 20:50:26 XXXX kernel: [37413.896477] usb 1-1.3: Manufacturer: SanDisk
Aug 26 20:50:26 XXXX kernel: [37413.896478] usb 1-1.3: SerialNumber: D90DE5177722B3980000000000000000
Aug 26 20:50:26 XXXX kernel: [37413.903417] usb-storage 1-1.3:1.0: USB Mass Storage device detected
Aug 26 20:50:26 XXXX kernel: [37413.916127] scsi host5: usb-storage 1-1.3:1.0
Aug 26 20:50:26 XXXX upowerd[2020]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3/1-1.3:1.0
Aug 26 20:50:26 XXXX upowerd[2020]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3
Aug 26 20:50:26 XXXX gvfsd[2856]: Device 0 (VID=0781 and PID=7430) is a SanDisk Sansa m240/m250.
Aug 26 20:50:26 XXXX gvfsd[2856]: LIBMTP PANIC: Could not open session! (Return code 8194)
Aug 26 20:50:26 XXXX gvfsd[2856]: Try to reset the device.
Aug 26 20:50:26 XXXX gnome-shell[2849]: Unable to mount volume SanDisk Sansa m240: Gio.IOErrorEnum: Unable to open MTP device “[usb:001,009]”
Aug 26 20:50:26 XXXX upowerd[2020]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3/1-1.3:1.0
Aug 26 20:50:26 XXXX upowerd[2020]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3/1-1.3:1.0
Aug 26 20:50:26 XXXX upowerd[2020]: unhandled action 'unbind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3/1-1.3:1.0
XXXX:~$ mtp-detect
libmtp version: 1.1.13
Listing raw device(s)
Device 0 (VID=0781 and PID=7430) is a SanDisk Sansa m240/m250.
Found 1 device(s):
SanDisk: Sansa m240/m250 (0781:7430) @ bus 1, dev 12
Attempting to connect device(s)
LIBMTP PANIC: Could not open session! (Return code 8194)
Try to reset the device.
Unable to open raw device 0
OK.
Anonymous
The following actions fixed my problem since I don't need MTP.
XXXX:~$ ls -ld /usr/lib/gvfs/gvfsd-mtp
-rwxr-xr-x 1 root root 71672 Jul 5 23:04 /usr/lib/gvfs/gvfsd-mtp
XXXX:~$ sudo chmod -x /usr/lib/gvfs/gvfsd-mtp
XXXX:~$ ls -ld /usr/lib/gvfs/gvfsd-mtp
-rw-r--r-- 1 root root 71672 Jul 5 23:04 /usr/lib/gvfs/gvfsd-mtp
XXXX:~$ tail -n NNN /var/log/syslog
Aug 27 14:29:11 XXXX kernel: [15704.594016] usb 1-1.3: new high-speed USB device number 4 using ehci-pci
Aug 27 14:29:11 XXXX kernel: [15704.710544] usb 1-1.3: New USB device found, idVendor=0781, idProduct=7430
Aug 27 14:29:11 XXXX kernel: [15704.710547] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
Aug 27 14:29:11 XXXX kernel: [15704.710548] usb 1-1.3: Product: SanDisk Sansa m240
Aug 27 14:29:11 XXXX kernel: [15704.710550] usb 1-1.3: Manufacturer: SanDisk
Aug 27 14:29:11 XXXX kernel: [15704.710551] usb 1-1.3: SerialNumber: D90DE5177722B3980000000000000000
Aug 27 14:29:11 XXXX kernel: [15704.728605] usb-storage 1-1.3:1.0: USB Mass Storage device detected
Aug 27 14:29:11 XXXX kernel: [15704.740450] scsi host5: usb-storage 1-1.3:1.0
Aug 27 14:29:11 XXXX gnome-shell[3821]: Unable to mount volume SanDisk Sansa m240: GLib.SpawnError: Failed to execute child process “/usr/lib/gvfs/gvfsd-mtp” (Permission denied)
Aug 27 14:29:11 XXXX upowerd[2245]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3/1-1.3:1.0
Aug 27 14:29:11 XXXX upowerd[2245]: unhandled action 'bind' on /sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.3
Aug 27 14:29:12 XXXX kernel: [15705.765563] scsi 5:0:0:0: Direct-Access SanDisk Sansa m240 v4.1 PQ: 0 ANSI: 0
Aug 27 14:29:12 XXXX kernel: [15705.765888] sd 5:0:0:0: Attached scsi generic sg3 type 0
Aug 27 14:29:12 XXXX kernel: [15705.768053] sd 5:0:0:0: [sdc] 1986048 512-byte logical blocks: (1.02 GB/970 MiB)
Aug 27 14:29:12 XXXX kernel: [15705.769173] sd 5:0:0:0: [sdc] Write Protect is off
Aug 27 14:29:12 XXXX kernel: [15705.769176] sd 5:0:0:0: [sdc] Mode Sense: 04 00 00 00
Aug 27 14:29:12 XXXX kernel: [15705.770301] sd 5:0:0:0: [sdc] No Caching mode page found
Aug 27 14:29:12 XXXX kernel: [15705.770305] sd 5:0:0:0: [sdc] Assuming drive cache: write through
Aug 27 14:29:12 XXXX kernel: [15705.780689] sdc:
Aug 27 14:29:12 XXXX kernel: [15705.787303] sd 5:0:0:0: [sdc] Attached SCSI removable disk
Aug 27 14:29:13 XXXX kernel: [15706.571175] FAT-fs (sdc): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
Aug 27 14:29:13 XXXX systemd[1]: Created slice system-clean\x2dmount\x2dpoint.slice.
Aug 27 14:29:13 XXXX systemd[1]: Started Clean the /media/XXXX/SANSA M240 mount point.
Aug 27 14:29:13 XXXX udisksd[972]: Mounted /dev/sdc at /media/XXXX/SANSA M240 on behalf of uid XXXX
XXXX:~$ df -TH |egrep 'Type|vfat'
Filesystem Type Size Used Avail Use% Mounted on
/dev/sdc vfat 1.1G 230M 787M 23% /media/XXXX/SANSA M240
Thank you - the solution worked for me as well!
The device is a mix between mass storage and MTP ... you selected the mass storage variant.
Hmm, hard to solve.