I spent the whole evening with Manu looking through the emulation layer and cannot see any obvious errors in the DVB-T case.
Thank-you very much for your time.
Then use VDR-1.4.x (limited to only one device) and tune to a certain DVB-T channel. Have a look what the driver reports (see dmesg or /var/log/messages or anything else which suits your system) at least for the set_frontend() function.
Next use VDR-1.5.12-dvbs2-... (limited to only one device) and tune to the same DVB-T channel. Check what the driver reports this time. Additionally to the set_frontend() output there must a similar output before it which shows the parameters which VDR passed to the emulation layer.
Please report the debug output here for further investigation.
Attached are two files - tuning to the same DVB-T channel using either system and the Philips frontend... vdr-1.4.x shows the channel fine, 1.5.12 does not.
Hope this helps and thanks again for your assistance.
Regards