Ok I ran the test. Here are my results:
SD Card Test
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SD card is connected
Card type is SDHC
File system space is 3972.01 Mbytes.
SD library is able to access the filesystem
Reading SDTEST1.WAV:
Overall speed = 0.74 Mbyte/sec
Worst block time = 1.32 ms
45.50% of audio frame time
Reading SDTEST1.WAV & SDTEST2.WAV:
Overall speed = 0.61 Mbyte/sec
Worst block time = 3.09 ms
106.47% of audio frame time
Reading SDTEST1.WAV & SDTEST2.WAV staggered:
Overall speed = 0.61 Mbyte/sec
Worst block time = 2.59 ms
89.13% of audio frame time
Reading SDTEST1.WAV, SDTEST2.WAV, SDTEST3.WAV:
Overall speed = 0.61 Mbyte/sec
Worst block time = 4.70 ms
162.10% of audio frame time
Reading SDTEST1.WAV, SDTEST2.WAV, SDTEST3.WAV staggered:
Overall speed = 0.61 Mbyte/sec
Worst block time = 3.50 ms
120.63% of audio frame time
Reading SDTEST1.WAV, SDTEST2.WAV, SDTEST3.WAV, SDTEST4.WAV:
Overall speed = 0.61 Mbyte/sec
Worst block time = 6.29 ms
216.83% of audio frame time
Reading SDTEST1.WAV, SDTEST2.WAV, SDTEST3.WAV, SDTEST4.WAV staggered:
Overall speed = 0.61 Mbyte/sec
Worst block time = 4.41 ms
151.96% of audio frame time