Unknown songs

I think that to start you need to figure out the source of the problem.  Do the same tracks always show up as unknown, or do some sometimes show up right and sometimes not.  I know you said randomly, but it's not clear just how random this is.   I'd start by going into the individual album folders and looking at the ripped files and seeing if they have been tagged properly, and looking at the artwork files.  I'd look at them with iTunes or another music player (Media Monkey) just to SEE how they show up.  If they show up other than fine, I'd use a tag editor and fix the tags and see if that fixes your issue. 

If ripped files from relatively mainstream cd's aren't getting tagged properly, it's often a problem with the ripper software being set to use some tag database that is inaccessible; most give you options of databases and you can just pick another.

So I'd start by seeing if it's a ripping problem, and if it's not, you have to look further downstream. If it's not a ripping problem someone else needs to help you as I know nothing about Asset

I certainly did not mean to imply that you have to "check every single time [you] rip a cd."  I was trying to suggest a protocol for finding your problem and fixing it.

Yes these things can be frustrating if not working properly.  Take a deep breath

I would suggest an educated guess is that the albums that are not showing properly have been ripped as wav.

I have found Monkeymedia (free version) to be a very useful half-way house for getting everything into proper shape for my Naim HDX, and also for Sonos which I'm using temporarily in another part of the house.

CDs ripped though my HDX are generally fine, though occasionally albums or tracks appear as "unknown" or artwork is not found.  It's worth the effort to check as you go, as it's easier to make the corrections manually while you've got the CD in front of you.

I also ripped my vinyl collection through the (free) Audacity program.  Unfortunately, Audacity did not tag the files correctly either for Naim or for Sonos and that's Mediamonkey came into its own.  It was fairly time-consuming but Mediamonkey was able to tag everything correctly and make the album art visible for both Naim and Sonos and I don't know how I'd have achieved this without it.  Mediamonkey is not, however, to be used for anything ripped through my HDX - I use only Desktop Client for this.

All my files are .wav.  I think Audacity works better if you rip to .flac but for one reason or another I've been a .wav man since the beginning.  Also, my Ipod (which I use when travelling to access the music on my NAS at home) won't play .flac files so I prefer to have everything in .wav. 

I agree that the networking malarkey can be tedious and frustrating but, once you've got over the initial hump, it requires only minor maintenance and the rewards are great.  It's fantastic to have all my music on one seamless database at my fingertips, wherever I am in the house and even away from it.

There is one thing that I find curious.  Very occasionally when I rip a CD on my HDX, I get a name and track listing that bears no relationship to the contents of the CD - Engelbert Humperdinck's Greatest Hits, for example (which I definitely don't own).  Do manufacturers re-use disks that they haven't been able to sell and fail to re-code them properly?  It doesn't seem to affect the music.

Try mp3tag free software which support flac format. Edit all your song with it. Check if the tags are correct and try again. If the problem persist, you may try adding some info in the comment tag for all the files and save. Mp3tag allows you to do a mass change. Through this the software will rewrite the tags and this may solve your problem. For the album artwork check if cover type is set as front cover. Hope it helps Sam

I second mp3tag as previous poster mentioned, I had 20 plus albums showing unknown, mp3tag sorted this plus it's free! Also I have multiple rips of the same album ie Dark Side of the Moon mp3tag enables you to retitle these albums so they all appear as separate titles under the artist.

Woodsman, you might be slightly confused.. Tagging is put in the file and not stored as the file name although you can let the file nam be made from the embedded tag info but that is to help you rather than the file reader.

This does possibly point to an issue of metadata look up. In dBpoweramp you can choose the precedence of database lookup. Also to access the AMG database from dbpoweramp, which is very comprehensive, a registration fee and licence  is needed.

Simon