After the privately released Dreamwavepatterns in 2000 and Rockstar in 2004, Humble Grumble issued 30 Years Kolinda on the Pan Records label in 2005. Vörös had become enamored of the music of Hungarian folk outfit Kolinda, and embarked on the 30 Years Kolinda project and album after meeting group mainstay Peter Dabasi in Budapest. To mark Kolinda's 30th anniversary, Vörös invited Dabasi to perform live with Humble Grumble, and, aside from one track, the associated 30 Years Kolinda album featured Dabasi compositions exclusively. The album also marked the arrival of several musicians who would remain key members of Humble Grumble in the future: saxophonist Pol Mareen, clarinetist Pedro Guridi, and bassist Jouni Isoherranen. Several years would pass between the release of 2005's 30 Years Kolinda and Humble Grumble's next album, The Face of Humble Grumble, which arrived in 2008 on the Cocktail Soul Productions label and featured re-recordings of material from Dreamwavepatterns and Rockstar. In addition to Vörös, Mareen, Guridi, and Isoherranen, the musicians on The Face of Humble Grumble also included Pieter Claus on marimba, Jonathan Callens on drums, and a pair of singers, Megan Quill and Franciska Roose, who good-naturedly harmonized with decidedly quirky frontman Vörös. From that point forward, Humble Grumble would settle into a lineup of guitar/vocals, saxophone, clarinet, marimba/vibraphone, bass, and drums, plus female vocal chorus and other guests.
Meanwhile, to the south in Milan, Italy, producer Marcello Marinone and friends at the AltrOck label were taking notice of Humble Grumble, and ultimately concluded that the group would fit in well with the imprint's avant-prog artist roster. Providing the group with its widest distribution yet, AltrOck released the ambitious yet crazily offbeat Flanders Fields CD in 2011; the album featured Vörös, Mareen, Guridi, Isoherranen, Claus, and Callens, plus Quill and Roose among a slew of 11 guest musicians, most of them vocalists. Two years later, Humble Grumble returned with their second AltrOck release, Guzzle It Up!, featuring the same basic core lineup plus guests; singer Quill was now deemed a full bandmember but Roose had departed, with Liesbeth Verlaet joining Quill in the band's female vocal duo (with matching nautical motif miniskirts and over-the-knee socks), and Joren Cautaers was the group's new vibraphonist, although Pieter Claus took a "guest" marimba solo on one track. ~ Dave Lynch, Rovi