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The frequencies of solar oscillation modes are correlated with activity levels, but the relationship between the frequencies and other activity proxies is not completely straightforward. In order to determine whether previously identified trends have persisted, changed, or disappeared through Cycle 24,
we have re-analysed the last 32 years of low-degree mode frequency data from the Birmingham Solar Oscillations Network. We confirm earlier findings that the lowest-frequency modes are less sensitive to activity in the last two solar cycles than they were in Cycle 22; we also find that the medium and higher frequencies are more sensitive to activity in Cycles 23 and 24. These differences in behaviour between Cycle 22 and the more recent cycles add to the growing body of evidence that something may be changing in the solar dynamo, perhaps related to thinning of the near-surface layer where the magnetic fields affect the mode frequencies, and/or to a greater proportion of weaker, more ephemeral active regions in the recent cycles.