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Geometric interference between these high-frequency waves produces a peak-like structure in the power spectrum of the star, known as the pseudo-modes. In this study, we aim to analyse 51 stars previously identified (from a sample of 91 Kepler stars) to contain statistically significant evidence for pseudo-modes, to determine if the pseudo-mode frequencies vary in time. We obtained these frequency variations and the uncertainty by the resampled periodogram approach, where periodogram realisations were created from successive, overlapping 90-d time segments, and a cross-correlation function was generated between them. The computed shifts were compared against temporal p-mode frequency shifts and a stellar magnetic activity proxy, $S_{\\mathrm{ph}}$. We found that for 16\u00a0per\u2009cent of the stars pseudo-mode frequency shifts were significantly anticorrelated with p-mode shifts, as is the case for the Sun. However, we also found pseudo-mode and p-mode shifts to be significantly correlated in-phase in 8\u00a0per\u2009cent of our sample. The remainder showed no significant correlation. We also searched for trends between the maximum variation of pseudo-mode frequency shifts and stellar parameters. Whilst we found no correlation between the maximum variation and stellar photospheric and chromospheric proxies, we found frequency variations to have a greater amplitude for cooler and slower rotating stars, which is in opposition to p-mode frequency shift variation. Temporal changes to pseudo-mode frequencies may be attributable to variations in stellar magnetic activity, and therefore can contribute to our understanding of stellar activity cycles.<\/jats:p>","DOI":"10.1093\/mnras\/staf050","type":"journal-article","created":{"date-parts":[[2025,1,12]],"date-time":"2025-01-12T04:32:51Z","timestamp":1736656371000},"page":"1268-1281","source":"Crossref","is-referenced-by-count":0,"title":["Investigation of oscillations above the acoustic cut-off frequency for a sample of <i>Kepler<\/i> stars. II. Identifying temporal frequency shifts"],"prefix":"10.1093","volume":"537","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-4254-2676","authenticated-orcid":false,"given":"L J","family":"Millson","sequence":"first","affiliation":[{"name":"Centre for Fusion, Space and Astrophysics (CFSA), Department of Physics, University of Warwick , Coventry, CV4 7AL ,","place":["UK"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5209-9378","authenticated-orcid":false,"given":"A-M","family":"Broomhall","sequence":"additional","affiliation":[{"name":"Centre for Fusion, Space and Astrophysics (CFSA), Department of Physics, University of Warwick , Coventry, CV4 7AL ,","place":["UK"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7195-6542","authenticated-orcid":false,"given":"A R G","family":"Santos","sequence":"additional","affiliation":[{"name":"Instituto de Astrof\u00edsica e Ci\u00eancias do Espa\u00e7o, Universidade do Porto, CAUP , Rua das Estrelas, P-4150-762 Porto ,","place":["Portugal"]},{"name":"Departamento de F\u00edsica e Astronomia, Faculdade de Ci\u00eancias, Universidade do Porto , Rua do Campo Alegre 687, P-4169-007 Porto ,","place":["Portugal"]}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4166-5343","authenticated-orcid":false,"given":"R","family":"Kiefer","sequence":"additional","affiliation":[{"name":"Fraunhofer Institute for High-Speed Dynamics, Ernst Mach Institute, EMI , Ernst-Zermelo-Stra\u00dfe 4, D-79104 Freiburg ,","place":["Germany"]}]},{"given":"M","family":"Jones","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Warwick , Coventry, CV4 7AL ,","place":["UK"]}]}],"member":"286","published-online":{"date-parts":[[2025,1,11]]},"reference":[{"key":"2025013114412599900_bib1","doi-asserted-by":"publisher","first-page":"173","DOI":"10.3847\/1538-4357\/835\/2\/173","volume":"835","author":"Aguirre","year":"2017","journal-title":"ApJ"},{"key":"2025013114412599900_bib2","doi-asserted-by":"publisher","first-page":"A33","DOI":"10.1051\/0004-6361\/201322068","volume":"558","author":"Astropy Collaboration","year":"2013","journal-title":"A&A"},{"key":"2025013114412599900_bib3","doi-asserted-by":"publisher","first-page":"123","DOI":"10.3847\/1538-3881\/aabc4f","volume":"156","author":"Astropy Collaboration","year":"2018","journal-title":"AJ"},{"key":"2025013114412599900_bib4","doi-asserted-by":"publisher","first-page":"167","DOI":"10.3847\/1538-4357\/ac7c74","volume":"935","author":"Astropy Collaboration","year":"2022","journal-title":"ApJ"},{"key":"2025013114412599900_bib5","doi-asserted-by":"publisher","first-page":"359","DOI":"10.1007\/s11214-014-0068-0","volume":"186","author":"Bazilevskaya","year":"2014","journal-title":"Space Sci. 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