AverTV Volar HD Pro scanning problems

Hello,

I use this device

07ca:a835 AVerMedia Technologies, Inc.

with a 3.1.2 kernel (x86_64). TV can be played just fine in Kaffeine, but scanning does not work (tried with kaffeine, scan). One has to obtain the channel information from elsewhere, since scanning ends with the following errors in dmesg:

	af9035: recv bulk message failed:-110
	af9033: I2C read failed reg:0047
	af9035: recv bulk message failed:-110
	af9033: I2C read failed reg:0045

	* Attempts to disable USB autosuspend (using the usbcore parameter and/or laptop-mode-tools) don't change anything.
	* Failures are less likely (occur later during the scan) if the device is plugged into a USB 3.0 port.

How can I make scanning work? Is there a Git branch I could try?

Thank you in advance for your hints. :-)

Andrej

P. S. The dmesg output after plugging in the device:

usb 4-1.2: new high speed USB device number 6 using ehci_hcd
dvb-usb: found a 'Avermedia AverTV Volar HD & HD PRO (A835)' in cold state, will try to load a firmware
dvb-usb: downloading firmware from file 'dvb-usb-af9035-01.fw'
dvb-usb: found a 'Avermedia AverTV Volar HD & HD PRO (A835)' in warm state.
dvb-usb: will pass the complete MPEG2 transport stream to the software demuxer.
DVB: registering new adapter (Avermedia AverTV Volar HD & HD PRO (A835))
af9033: firmware version: LINK:11.15.10.0 OFDM:5.48.10.0
DVB: registering adapter 0 frontend 0 (Afatech AF9033 DVB-T)...
tda18218: NXP TDA18218HN successfully identified.
IR keymap rc-avermedia-rm-ks not found
Registered IR keymap rc-empty
input: IR-receiver inside an USB DVB receiver as /devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1.2/rc/rc3/input19
rc3: IR-receiver inside an USB DVB receiver as /devices/pci0000:00/0000:00:1d.0/usb4/4-1/4-1.2/rc/rc3
dvb-usb: schedule remote query interval to 400 msecs.
dvb-usb: Avermedia AverTV Volar HD & HD PRO (A835) successfully initialized and connected.