Although there is a push to provide more student agency in science classrooms, teachers and students may become frustrated when inquiry activities and equipment do not work as planned--teachers because of the time crunch to "cover" topics and students because of the perceived lack of value in activities that are "off task." In classroom implementations of a data-rich high school physics activity sequence as part of the InquirySpace 2 (IS2) project, numerous episodes of equipment troubleshooting were observed. Teachers questioned whether the time spent had disciplinary value. Students expressed concern regarding what, if anything, they were learning. This qualitative case study of one such episode considers students' activity in terms of their engagement with the "mangle of practice" and misalignments between their conceptual and material worlds, their exercise of epistemic agency in recognizing and repairing those misalignments, and their epistemic affect during and after the activity. Video analysis revealed all three aspects deeply intertwined with evidence of student engagement in multiple science practices. The students expressed their feelings about the episode immediately afterward and the teacher and IS2 observer when interviewed much later, at the end of the project. One reason for the negative perceptions of teacher and students may be that the alignments being explored were related to the instrumentation more than to the target phenomenon. This study argues that in such situations, students may not recognize or value science practices that emerge, and may need explicit support to reframe their activity as valid scientific practice.