COMMAND_UPDATE_PLAYBACK_STREAM_SAMPLE_RATE is ineffective

Version, Distribution, Desktop Environment: pipewire-pulseaudio-0.3.27-1.fc34.x86_64, Fedora 34, Gnome on X11.

Description of Problem: I have some code that (in certain circumstances) starts a stream at 48 kHz and then later tries to adjust it to 44.1 kHz by calling pa_stream_update_sample_rate(). I believe that this worked on Fedora 33 with PulseAudio, but it doesn’t work on Fedora 34 with PipeWire.

The following appears in journalctl --user, suggesting that the message is getting through to the daemon:

pipewire-pulse[2808]: pulse-server 0x55a382d68d90: [SqueezeLite] UPDATE_PLAYBACK_STREAM_SAMPLE_RATE tag:35 channel:0 rate:44100

However, pw-top shows that the sample rate remains at 48000:

S   ID  QUANT   RATE    WAIT    BUSY   W/Q   B/Q  ERR  NAME
…
    50   4096  48000 665.9µs  26.8µs  0.01  0.00    8  alsa_output.pci-0000_0b_02.0.analog-stereo-speaker
    29  10080  48000 111.9µs 450.5µs  0.00  0.01    8   + SqueezeLite

How Reproducible: Always.

Actual Results: Audio plays too quickly. Singers sound like chipmunks.

Expected Results: Audio plays at the correct rate and sounds normal.