[HTC U12+ Questions & Answers] AtAM1:
Update 2: I managed to get the getprop values from Oreo 1.53 - key differences are HTC seems to have either dropped or forgotten to add and/or port over vendor specific values to Pie, specifically:

Missing Properties / Values in Pie [Audio related]

-[persist.vendor.audio.fluence.speaker]: [true]
-[persist.vendor.audio.fluence.voicecall]: [true]
-[persist.vendor.audio.fluence.voicerec]: [false]
-[persist.vendor.audio.headset.anc.type]: [feedback]
-[persist.vendor.audio.ras.enabled]: [false]
-[vendor.audio.adm.buffering.ms]: [2]
-[vendor.audio.dolby.ds2.enabled]: [false]
-[vendor.audio.dolby.ds2.hardbypass]: [false]
-[vendor.audio.enable.dp.for.voice]: [false]
-[vendor.audio.flac.sw.decoder.24bit]: [true]
-[vendor.audio.hw.aac.encoder]: [true]
-[vendor.audio.noisy.broadcast.delay]: [600]
-[vendor.audio.offload.buffer.size.kb]: [1024]
-[vendor.audio.offload.multiaac.enable]: [true]
-[vendor.audio.offload.multiple.enabled]: [true]
-[vendor.audio.offload.passthrough]: [false]
-[vendor.audio.offload.pstimeout.secs]: [3]
-[vendor.audio.offload.track.enable]: [true]
-[vendor.audio.parser.ip.buffer.size]: [262144]
-[vendor.audio.safx.pbe.enabled]: [true]
-[vendor.audio.tunnel.encode]: [false]
-[vendor.audio.use.sw.alac.decoder]: [true]
-[vendor.audio.use.sw.ape.decoder]: [true]
-[vendor.voice.path.for.pcm.voip]: [true]

Unchanged Properties / Values in Pie [Audio related]

[persist.audio.fluence.speaker]: [true]
[persist.audio.fluence.voicecall]: [true]
[persist.audio.fluence.voicerec]: [false]
[vendor.audio_hal.in_period_size]: [144]
[vendor.audio_hal.period_multiplier]: [3]
[vendor.audio_hal.period_size]: [192]

New Properties / Values in Pie [Audio related]

+[media.stagefright.audio.deep]: [true]

Another major change to how the microphone is managed under pie (audio_platform_info.xml)-

@@ -239,6 +239,7 @@
<usecase name="USECASE_AUDIO_RECORD_LOW_LATENCY" type="in" id="17" />
<usecase name="USECASE_AUDIO_PLAYBACK_ULL" type="out" id="17" />
<usecase name="USECASE_AUDIO_PLAYBACK_EXT_DISP_SILENCE" type="out" id="27" />
+ <usecase name="USECASE_AUDIO_A2DP_ABR_FEEDBACK" type="in" id="40" />
</pcm_ids>
<config_params>
<param key="spkr_1_tz_name" value="wsatz.13"/>
@@ -349,6 +350,388 @@
<device name="SND_DEVICE_IN_HEADSET_AS20_AMBIENT" interface="SLIMBUS_0_TX"/>
<!-- HTC BACKEND END -->
</backend_names>
+ <!-- below values are hardware info from audio HW team: Kevin.BH@20190329 -->
+ <microphone_characteristics>
+ <microphone valid_mask="31" device_id="builtin_mic_1" type="AUDIO_DEVICE_IN_BUILTIN_MIC" address="bottom" location="AUDIO_MICROPHONE_LOCATION_MAINBODY"
+ group="0" index_in_the_group="0" directionality="AUDIO_MICROPHONE_DIRECTIONALITY_OMNI" num_frequency_responses="93"
+ frequencies="100.00 106.00 112.00 118.00 125.00 132.00 140.00 150.00 160.00 170.00 180.00 190.00 200.00 212.00 224.00 236.00 250.00 265.00 280.00 300.00 315.00 335.00 355.00 375.00 400.00 425.00 450.00 475.00 500.00 530.00 560.00 600.00 630.00 670.00 710.00 750.00 800.00 850.00 900.00 950.00 1000.00 1060.00 1120.00 1180.00 1250.00 1320.00 1400.00 1500.00 1600.00 1700.00 1800.00 1900.00 2000.00 2120.00 2240.00 2360.00 2500.00 2650.00 2800.00 3000.00 3150.00 3350.00 3550.00 3750.00 4000.00 4250.00 4500.00 4750.00 5000.00 5300.00 5600.00 6000.00 6300.00 6700.00 7100.00 7500.00 8000.00 8500.00 9000.00 9500.00 10000.00 10600.00 11200.00 11800.00 12500.00 13200.00 14000.00 15000.00 16000.00 17000.00 18000.00 19000.00 20000.00"
+ responses="-0.9 -0.9 -0.8 -0.7 -0.5 -0.4 -0.7 -0.4 -0.6 -0.6 -0.6 -0.7 -0.7 -0.8 -0.6 -0.4 -0.5 -0.6 -0.6 -0.3 -0.5 -0.7 -0.5 -0.7 -0.7 -0.7 -0.7 -0.7 -0.6 -0.5 -0.4 -0.4 -0.5 -0.3 -0.2 -0.6 -0.8 -0.7 -0.5 -0.2 0.0 0.1 1.0 1.4 1.6 1.5 1.5 1.9 2.1 2.2 2.4 2.6 2.8 2.9 3.0 2.8 2.7 3.1 3.4 3.2 3.3 4.0 5.2 6.5 7.2 9.7 10.4 9.1 8.2 11.4 13.8 17.1 18.9 17.1 18.9 17.7 24.0 22.6 25.4 23.1 24.0 16.2 14.5 11.8 9.3 5.1 5.2 5.1 5.3 5.6 5.8 5.2 5.1"
+ sensitivity="-37.0" max_spl="132.5" min_spl="28.5" orientation="0.0 -1.0 0.0" geometric_location="0.0510 0.0 0.0022" />
+ <microphone valid_mask="31" device_id="builtin_mic_2" type="AUDIO_DEVICE_IN_BACK_MIC" address="back" location="AUDIO_MICROPHONE_LOCATION_MAINBODY"
+ group="0" index_in_the_group="1" directionality="AUDIO_MICROPHONE_DIRECTIONALITY_OMNI" num_frequency_responses="93"
+ frequencies="100.00 106.00 112.00 118.00 125.00 132.00 140.00 150.00 160.00 170.00 180.00 190.00 200.00 212.00 224.00 236.00 250.00 265.00 280.00 300.00 315.00 335.00 355.00 375.00 400.00 425.00 450.00 475.00 500.00 530.00 560.00 600.00 630.00 670.00 710.00 750.00 800.00 850.00 900.00 950.00 1000.00 1060.00 1120.00 1180.00 1250.00 1320.00 1400.00 1500.00 1600.00 1700.00 1800.00 1900.00 2000.00 2120.00 2240.00 2360.00 2500.00 2650.00 2800.00 3000.00 3150.00 3350.00 3550.00 3750.00 4000.00 4250.00 4500.00 4750.00 5000.00 5300.00 5600.00 6000.00 6300.00 6700.00 7100.00 7500.00 8000.00 8500.00 9000.00 9500.00 10000.00 10600.00 11200.00 11800.00 12500.00 13200.00 14000.00 15000.00 16000.00 17000.00 18000.00 19000.00 20000.00"
+ responses="-0.9 -0.9 -0.8 -0.7 -0.5 -0.4 -0.7 -0.4 -0.6 -0.6 -0.6 -0.7 -0.7 -0.8 -0.6 -0.4 -0.5 -0.6 -0.6 -0.3 -0.5 -0.7 -0.5 -0.7 -0.7 -0.7 -0.7 -0.7 -0.6 -0.5 -0.4 -0.4 -0.5 -0.3 -0.2 -0.6 -0.8 -0.7 -0.5 -0.2 0.0 0.1 1.0 1.4 1.6 1.5 1.5 1.9 2.1 2.2 2.4 2.6 2.8 2.9 3.0 2.8 2.7 3.1 3.4 3.2 3.3 4.0 5.2 6.5 7.2 9.7 10.4 9.1 8.2 11.4 13.8 17.1 18.9 17.1 18.9 17.7 24.0 22.6 25.4 23.1 24.0 16.2 14.5 11.8 9.3 5.1 5.2 5.1 5.3 5.6 5.8 5.2 5.1"
+ sensitivity="-37.0" max_spl="132.5" min_spl="28.5" orientation="0.0 0.0 1.0" geometric_location="0.037 0.0195 0.0024" />
+ <microphone valid_mask="31" device_id="builtin_mic_3" type="AUDIO_DEVICE_IN_BUILTIN_MIC" address="front" location="AUDIO_MICROPHONE_LOCATION_MAINBODY"
+ group="0" index_in_the_group="2" directionality="AUDIO_MICROPHONE_DIRECTIONALITY_OMNI" num_frequency_responses="93"
+ frequencies="100.00 106.00 112.00 118.00 125.00 132.00 140.00 150.00 160.00 170.00 180.00 190.00 200.00 212.00 224.00 236.00 250.00 265.00 280.00 300.00 315.00 335.00 355.00 375.00 400.00 425.00 450.00 475.00 500.00 530.00 560.00 600.00 630.00 670.00 710.00 750.00 800.00 850.00 900.00 950.00 1000.00 1060.00 1120.00 1180.00 1250.00 1320.00 1400.00 1500.00 1600.00 1700.00 1800.00 1900.00 2000.00 2120.00 2240.00 2360.00 2500.00 2650.00 2800.00 3000.00 3150.00 3350.00 3550.00 3750.00 4000.00 4250.00 4500.00 4750.00 5000.00 5300.00 5600.00 6000.00 6300.00 6700.00 7100.00 7500.00 8000.00 8500.00 9000.00 9500.00 10000.00 10600.00 11200.00 11800.00 12500.00 13200.00 14000.00 15000.00 16000.00 17000.00 18000.00 19000.00"
+ responses="-0.9 -0.9 -0.8 -0.7 -0.5 -0.4 -0.7 -0.4 -0.6 -0.6 -0.6 -0.7 -0.7 -0.8 -0.6 -0.4 -0.5 -0.6 -0.6 -0.3 -0.5 -0.7 -0.5 -0.7 -0.7 -0.7 -0.7 -0.7 -0.6 -0.5 -0.4 -0.4 -0.5 -0.3 -0.2 -0.6 -0.8 -0.7 -0.5 -0.2 0.0 0.1 1.0 1.4 1.6 1.5 1.5 1.9 2.1 2.2 2.4 2.6 2.8 2.9 3.0 2.8 2.7 3.1 3.4 3.2 3.3 4.0 5.2 6.5 7.2 9.7 10.4 9.1 8.2 11.4 13.8 17.1 18.9 17.1 18.9 17.7 24.0 22.6 25.4 23.1 24.0 16.2 14.5 11.8 9.3 5.1 5.2 5.1 5.3 5.6 5.8 5.2 5.1"
+ sensitivity="-37.0" max_spl="132.5" min_spl="28.5" orientation="0.0 0.0 -1.0" geometric_location="0.0235 0.1445 0.0022" />
+ <microphone valid_mask="31" device_id="builtin_mic_4" type="AUDIO_DEVICE_IN_BUILTIN_MIC" address="top" location="AUDIO_MICROPHONE_LOCATION_MAINBODY"
+ group="0" index_in_the_group="3" directionality="AUDIO_MICROPHONE_DIRECTIONALITY_OMNI" num_frequency_responses="93"
+ frequencies="100.00 106.00 112.00 118.00 125.00 132.00 140.00 150.00 160.00 170.00 180.00 190.00 200.00 212.00 224.00 236.00 250.00 265.00 280.00 300.00 315.00 335.00 355.00 375.00 400.00 425.00 450.00 475.00 500.00 530.00 560.00 600.00 630.00 670.00 710.00 750.00 800.00 850.00 900.00 950.00 1000.00 1060.00 1120.00 1180.00 1250.00 1320.00 1400.00 1500.00 1600.00 1700.00 1800.00 1900.00 2000.00 2120.00 2240.00 2360.00 2500.00 2650.00 2800.00 3000.00 3150.00 3350.00 3550.00 3750.00 4000.00 4250.00 4500.00 4750.00 5000.00 5300.00 5600.00 6000.00 6300.00 6700.00 7100.00 7500.00 8000.00 8500.00 9000.00 9500.00 10000.00 10600.00 11200.00 11800.00 12500.00 13200.00 14000.00 15000.00 16000.00 17000.00 18000.00 19000.00"
+ responses="-0.9 -0.9 -0.8 -0.7 -0.5 -0.4 -0.7 -0.4 -0.6 -0.6 -0.6 -0.7 -0.7 -0.8 -0.6 -0.4 -0.5 -0.6 -0.6 -0.3 -0.5 -0.7 -0.5 -0.7 -0.7 -0.7 -0.7 -0.7 -0.6 -0.5 -0.4 -0.4 -0.5 -0.3 -0.2 -0.6 -0.8 -0.7 -0.5 -0.2 0.0 0.1 1.0 1.4 1.6 1.5 1.5 1.9 2.1 2.2 2.4 2.6 2.8 2.9 3.0 2.8 2.7 3.1 3.4 3.2 3.3 4.0 5.2 6.5 7.2 9.7 10.4 9.1 8.2 11.4 13.8 17.1 18.9 17.1 18.9 17.7 24.0 22.6 25.4 23.1 24.0 16.2 14.5 11.8 9.3 5.1 5.2 5.1 5.3 5.6 5.8 5.2 5.1"
+ sensitivity="-37.0" max_spl="132.5" min_spl="28.5" orientation="0.0 1.0 0.0" geometric_location="0.0546 0.1456 0.00415" />
+ </microphone_characteristics>

.... continued see attached file.

Could you respond to HTC and share the above with them so it is escalated to their dev team for an urgent fix release?

Thanks