Kaffeine - television - Configure Television - Device tab ...... is your DVB device listed on this tab?
Unplug the device, wait about 30 secs, plug it back in again, and run
dmesg
Copy and paste the last 25 lines or so of the output, into your next post.
Make sure you include all lines relating to the device being plugged in again.
An example, using a different device .......
dvb-usb: Afatech AF9015 DVB-T USB2.0 stick successfully deinitialized and disconnected. <### this shows the disconnect of the device>
usb 1-6: new high-speed USB device number 15 using ehci_hcd <## plugged in again>
usb 1-6: New USB device found, idVendor=15a4, idProduct=9016
usb 1-6: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-6: Product: DVB-T 2
usb 1-6: Manufacturer: Afatech
usb 1-6: SerialNumber: 010101010600001
dvb-usb: found a 'Afatech AF9015 DVB-T USB2.0 stick' in cold state, will try to load a firmware
dvb-usb: downloading firmware from file 'dvb-usb-af9015.fw' <## it gets its firmware file>
dvb-usb: found a 'Afatech AF9015 DVB-T USB2.0 stick' in warm state.
dvb-usb: will pass the complete MPEG2 transport stream to the software demuxer.
DVB: registering new adapter (Afatech AF9015 DVB-T USB2.0 stick)
af9013: firmware version:4.95.0.0
DVB: registering adapter 0 frontend 0 (Afatech AF9013 DVB-T)...
tda18218: NXP TDA18218HN successfully identified. <## the tuner is recognised>
Registered IR keymap rc-empty
input: IR-receiver inside an USB DVB receiver as /devices/pci0000:00/0000:00:0b.1/usb1/1-6/rc/rc1/input15
rc1: IR-receiver inside an USB DVB receiver as /devices/pci0000:00/0000:00:0b.1/usb1/1-6/rc/rc1
dvb-usb: schedule remote query interval to 500 msecs.
dvb-usb: Afatech AF9015 DVB-T USB2.0 stick successfully initialized and connected. <## Success!>
Afatech DVB-T 2: Fixing fullspeed to highspeed interval: 10 -> 7
input: Afatech DVB-T 2 as /devices/pci0000:00/0000:00:0b.1/usb1/1-6/1-6:1.1/input/input16
generic-usb 0003:15A4:9016.0008: input,hidraw0: USB HID v1.01 Keyboard [Afatech DVB-T 2] on usb-0000:00:0b.1-6/input1