As I got a little desperate that I'd never see the gui again for more then 10 seconds (on my production system no less), I have temporarily "fixed" this by getting a list of all mobile phone MAC numbers from the PnpQueue table, cleaning out the duplicates and inserting them into the UnknownDevices table. Very crude, but it worked for me.
Things work a lot smoother again, so clicking "always ignore" a few times every now and then isn't so much hassle anymore. I never would have guessed that there are such enormous amounts of bleutooth devices passing by my house every day (almost 4000 unique so far).
As I was writing this I figured the things I did might be kept in the shell's history so just for reference:
mysql pluto_main -e "SELECT MACaddress FROM PnpQueue WHERE Category='mobile_phone';" >mobile-mac.text
sort -u mobile-mac.text >mobile-mac_sorted.text
xargs --arg-file=mobile-mac_sorted.text insert_unknownDevice.sh
Where insert_unknownDevice.sh was a little script I made just for the occasion:
mysql pluto_main -e "INSERT INTO UnknownDevices VALUES (0,NULL,'$1','',NULL,'',1,NULL,NULL,NULL,0,NOW(),NULL);"
It can probably be done in a single SQL query, but I didn't feel like putting in more effort then needed. As you can see this is not for the fainthearted, and I wouldn't reccommend messing with the database directly unless you have no other option. Apart from that, this is likely not entirely the proper way of doing it anyway.