List evaluation problems

[Mario Domgörgen]

Hejhej group!

Are elisp problems on-topic are? Hope so ...

In the moment i'm working on a cd ripper and ogg-vorbis encoder for
emacs and it's almost done. Only one problem..

I want to make it a little more user-costumizable and removed some
hardcoded parts, so for example the ripping switches. Here's the old
working function (a little ripped down to the important parts):

(defun oggel-rip-track (tracknumber)
  (let ((proc (apply 'start-process (concat "oggel-ripping-" tracknumber)
                     "*Oggel*" oggel-ripping-programm 
                     "-t" tracknumber "-D" oggel-device "-x"
                     (list 
                      (oggel-create-trackname)))
                     )))
                     [...]                
    proc))

So and now my idea:

(defcustom oggel-ripping-switches 
  '("-D" oggel-device "-x" "-t" tracknumber) ; oggel-device and
  ;tracknumber are just strings

(defun oggel-rip-track (tracknumber)
  (let ((proc (apply 'start-process (concat "oggel-ripping-" 
                     oggel-current-tracknumber)
                     "*Oggel*" oggel-ripping-programm 
                     (append 
                      oggel-ripping-switches
                     (list 
                      (oggel-create-trackname)))
                     )))
                     [...]                
    proc))

But that just gives me:

(wrong-type-argument sequencep oggel-device)

I'm rather helpless as this is my first real elisp program. 

It would be great if somebody could help me with that!

Mario

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