I received a response from @WiiM Support.
quotation;
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1. WiiM Mini: The "Amazon Music HD/UHD" function is displayed within the WiiM HOME app when using the WiiM Mini. This allows you to toggle the HD/UHD functionality on or off as needed.
2. WiiM Pro: The Amazon Music HD/UHD setting is enabled by default and is not displayed in the app interface, as the Pro automatically supports HD/UHD playback.
3. Multi-Room Music (MRM) with Mini: When grouping multiple rooms (MRM) using the Mini, it is necessary to turn off the Amazon Music HD/UHD function to ensure normal playback. This is specific to the Mini and does not affect the Pro.
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This is consistent with what @Brantome explained, and I know he's right. However, it doesn't seem to work as described in my test.
I'm going to post my test results here to explain to the WiiM Team. I'm not sure if this is an issue that is only happening to my Mini, so I'd be happy if someone could test it the same way.
1. Link Mini and Pro to MRM.

2. Turn off "Amazon music HD/UHD" in Amazon Alexa settings on Mini.

3. Play Amazon music on WHA.
(Result is HD)

4. Play with AlexaCast.
(Result is SD)

There are a couple of questions here.
1. Why use the UHD switch in Alexa settings for MRM?
2. Does UHD Switch work for streaming services other than Amazon music?
[edit]
3. Are these behaviors normal because the choppy issues only occur when playing through Alexa?
Thank you.
quotation;
--------------------------------
1. WiiM Mini: The "Amazon Music HD/UHD" function is displayed within the WiiM HOME app when using the WiiM Mini. This allows you to toggle the HD/UHD functionality on or off as needed.
2. WiiM Pro: The Amazon Music HD/UHD setting is enabled by default and is not displayed in the app interface, as the Pro automatically supports HD/UHD playback.
3. Multi-Room Music (MRM) with Mini: When grouping multiple rooms (MRM) using the Mini, it is necessary to turn off the Amazon Music HD/UHD function to ensure normal playback. This is specific to the Mini and does not affect the Pro.
--------------------------------
This is consistent with what @Brantome explained, and I know he's right. However, it doesn't seem to work as described in my test.
I'm going to post my test results here to explain to the WiiM Team. I'm not sure if this is an issue that is only happening to my Mini, so I'd be happy if someone could test it the same way.
1. Link Mini and Pro to MRM.

2. Turn off "Amazon music HD/UHD" in Amazon Alexa settings on Mini.

3. Play Amazon music on WHA.
(Result is HD)

4. Play with AlexaCast.
(Result is SD)

There are a couple of questions here.
1. Why use the UHD switch in Alexa settings for MRM?
2. Does UHD Switch work for streaming services other than Amazon music?
[edit]
3. Are these behaviors normal because the choppy issues only occur when playing through Alexa?

Thank you.

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