Not 'no interest', but 'no success'.

I had tried to find songs from the Kriegsmarine (not my type of songs). It is easy to find on the web a list of titles (no indication of convoy hunting in the titles), but I had a hard time finding lyrics. The only two I located were rather unspecific like (transl.) 'We sail against England' and so I didn't post.

In the title lists there are a couple of submarine songs and I guess in one or two of them will be allusions to convoys, but as I said, no luck with lyrics so far.

While writing this bit I got a new search idea and here you are, a German WWII submarine song mentioning waiting for convoys:

Das U-Bootlied

the relevant part of the German lyrics:
Die Tage gehen vorbei
in ewgem Einerlei
- aber Beute gibt's noch immer nicht.
Da plötzlich tönt Alarm vom Turm!
Ein großer Geleitzug
schiebt schwer durch den Sturm!
Jetzt kommt es auf jedes Lederpäcken an
Vom Kaleu bis zum letzten Mann.

rough translation:

The days go by
none of them any different
but there is still no prey (prize)
There all of a sudden alarm sounds from the tower(?; the uppermost part of a submarine however you call it)
a big convoy
rolls through the storm
now it's up to each submarine man
from captain to the last man.

There are more songs, but that's the only one mentioning convoys

Wolfgang