The Soldiers could not go past SS Assad, who beat them 5-4 on a post-match penalty after a barren draw in regulation time.
Nationwide side Bungoma All-Stars also beat former KPL champions Sofapaka 5-4 in another penalty shootout contest staged away in Bungoma.
Meanwhile, Kariobangi Sharks pumped five goals past a hapless Education FC to kick off the FKF Shield title defense on a high note.
Erick Kapaito was on the score sheet for the second match running with the second goal of the day after Henry Juma had given them a deserved lead in the 38th-minute.
Meanwhile, AFC Leopards beat Kitale Transfoc 4-0. Vincent Oburu, Bonventure Kaheza, Brian Marita and Isaac Oduro were all on target to hand coach Casa Mbungo a strong start in the knockout competition.
Elsewhere, Benjamin Mosha's lone goal helped Bandari overcome a resilient Kayo FC from Marsabit to sail into the next round.
Round of 32 results for Saturday: Uprising 0-5 Western Stima (Ruaraka Grounds), Congo Boys 2(3)-2(2) Kenya Police (Serani Sports Grounds), SS Assad 0(5)-0(4) Ulinzi Stars (Ukunda Show Grounds), Bungoma Superstars 0(5)-0(4) Sofapaka (Sudi Stadium), Muranga Seal 4-1 Kisumu All Stars (Kiharu Stadium), Transmara Sugar vs Bidco United (Gusii Stadium), Dero 2-0 FC Talanta (Moi Stadium Kisumu), Sindo United 0-1 KCB (Moi Stadium Kisumu), Vihiga Sportif 2-0 Ushuru (Mumias), Elim 0-5 Kariobangi Sharks (Bukhungu), Transfoc 0-4 AFC Leopards (Bukhungu) and Kayo 0-1 Bandari (Ruaraka).