Why does secure rip some tracks twice on one occasion, but once on others?

[blackcherry]

I just inserted a brand new CD and I noticed that the drive was ripping at a slower speed than usual, but it had passed through the first track correctly once. I stopped the drive thinking that my drive was set to quiet mode, and set it to performance mode. When I reinserted the disc, it ripped the track I just ripped through two passes this time. Why did dbpoweramp show this random behavior?
I'm on Mac OS X 10.9 and using a Pioneer BDR-XD05S drive. Here's the log for the problematic second rip:

dBpoweramp  Digital Audio Extraction Log from 2017-02:25 21:21:54

Drive & Settings
----------------

Ripping with drive 'disk1   [PIONEER - BD-RW   BDR-XD05]',  Drive offset: 667,  Overread Lead-in/out: No
AccurateRip: Active,  Using C2: No,  Cache: 4000 KB,  FUA Cache Invalidate: No
Pass 1 Drive Speed: Max,  Pass 2 Drive Speed: Max
Ultra::  Vary Drive Speed: No,  Min Passes: 3,  Max Passes: 6,  Finish After Clean Passes: 3
Bad Sector Re-rip::  Drive Speed: Max,  Maximum Re-reads: 34

Encoder: Apple Lossless 

Extraction Log
--------------

Track 1:  Ripped LBA 0 to 21998 (4:53) in 1:04. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/01 Ladytron - High Rise.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 8B918EE4     AccurateRip CRC: FE8AF665 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-1]
  AccurateRip Verified Confidence 4 [CRCv2 fe8af665]
  AccurateRip Verified Confidence 6 [CRCv2 da58122d], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 c275f8ae], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 fe8af665]

Track 2:  Ripped LBA 21998 to 42737 (4:36) in 0:05. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/02 Ladytron - Destroy Everything You Touch.m4a
    [Pass 1]
  CRC32: 7A60A4AE     AccurateRip CRC: 00000000     [DiscID: 017-002b398a-0224b68c-0011d411-2]

--------------

User Stopped Ripping


====================

dBpoweramp  Digital Audio Extraction Log from 2017-02:25 21:24:24

Drive & Settings
----------------

Ripping with drive 'disk1   [PIONEER - BD-RW   BDR-XD05]',  Drive offset: 667,  Overread Lead-in/out: No
AccurateRip: Active,  Using C2: No,  Cache: 4000 KB,  FUA Cache Invalidate: No
Pass 1 Drive Speed: Max,  Pass 2 Drive Speed: Max
Ultra::  Vary Drive Speed: No,  Min Passes: 3,  Max Passes: 6,  Finish After Clean Passes: 3
Bad Sector Re-rip::  Drive Speed: Max,  Maximum Re-reads: 34

Encoder: Apple Lossless 

Extraction Log
--------------

Track 1:  Ripped LBA 0 to 21998 (4:53) in 2:08. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/01 Ladytron - High Rise.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1 & 2]
  CRC32: 8B918EE4     AccurateRip CRC: FE8AF665 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-1]
  AccurateRip Verified Confidence 4 [CRCv2 fe8af665]

Track 2:  Ripped LBA 21998 to 42737 (4:36) in 0:54. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/02 Ladytron - Destroy Everything You Touch.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: FBD0F8EC     AccurateRip CRC: A42E8607 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-2]
  AccurateRip Verified Confidence 4 [CRCv2 a42e8607]
  AccurateRip Verified Confidence 6 [CRCv2 8f8522be], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 cd03cd44], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 a42e8607]

Track 3:  Ripped LBA 42737 to 62020 (4:17) in 0:46. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/03 Ladytron - International Dateline.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 0EDC98FF     AccurateRip CRC: 7CA9D508 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-3]
  AccurateRip Verified Confidence 4 [CRCv2 7ca9d508]
  AccurateRip Verified Confidence 6 [CRCv2 729cabf3], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 2abf0eb2], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 7ca9d508]

Track 4:  Ripped LBA 62020 to 86024 (5:20) in 0:53. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/04 Ladytron - Soft Power.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 71CC36DF     AccurateRip CRC: 998403FF (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-4]
  AccurateRip Verified Confidence 4 [CRCv2 998403ff]
  AccurateRip Verified Confidence 6 [CRCv2 5be0bdf4], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 2c5c102c], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 998403ff]

Track 5:  Ripped LBA 86024 to 94259 (1:49) in 0:35. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/05 Ladytron - CMYK.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1 & 2]
  CRC32: B85CD48B     AccurateRip CRC: 0D949F65 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-5]
  AccurateRip Verified Confidence 4 [CRCv2 d949f65]

Track 6:  Ripped LBA 94259 to 109774 (3:26) in 0:31. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/06 Ladytron - AMTV.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 670571B3     AccurateRip CRC: F2B38FD7 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-6]
  AccurateRip Verified Confidence 4 [CRCv2 f2b38fd7]
  AccurateRip Verified Confidence 6 [CRCv2 58ea940b], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 e76109f8], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 f2b38fd7]

Track 7:  Ripped LBA 109774 to 122595 (2:50) in 0:25. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/07 Ladytron - Sugar.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 86C85C1A     AccurateRip CRC: F6B7E0A5 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-7]
  AccurateRip Verified Confidence 4 [CRCv2 f6b7e0a5]
  AccurateRip Verified Confidence 6 [CRCv2 c643873c], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 c717a6c8], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 f6b7e0a5]

Track 8:  Ripped LBA 122595 to 140581 (3:59) in 0:34. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/08 Ladytron - Fighting In Built Up Areas.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 05E60301     AccurateRip CRC: 290C3D4B (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-8]
  AccurateRip Verified Confidence 4 [CRCv2 290c3d4b]
  AccurateRip Verified Confidence 6 [CRCv2 946da3a0], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 61192289], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 290c3d4b]

Track 9:  Ripped LBA 140581 to 154983 (3:12) in 0:26. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/09 Ladytron - The Last One Standing.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: EA0BCAEE     AccurateRip CRC: 74BBE131 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-9]
  AccurateRip Verified Confidence 4 [CRCv2 74bbe131]
  AccurateRip Verified Confidence 6 [CRCv2 e3310866], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 a5967125], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 74bbe131]

Track 10:  Ripped LBA 154983 to 172785 (3:57) in 0:31. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/10 Ladytron - Weekend.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: F4613B9D     AccurateRip CRC: B1069819 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-10]
  AccurateRip Verified Confidence 4 [CRCv2 b1069819]
  AccurateRip Verified Confidence 6 [CRCv2 5cadd045], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 acf215bb], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 b1069819]

Track 11:  Ripped LBA 172785 to 192553 (4:23) in 0:33. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/11 Ladytron - Beauty*2.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 58C5D05F     AccurateRip CRC: C70D1F00 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-11]
  AccurateRip Verified Confidence 4 [CRCv2 c70d1f00]
  AccurateRip Verified Confidence 6 [CRCv2 607fe7ab], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 d3809571], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 c70d1f00]

Track 12:  Ripped LBA 192553 to 210548 (3:59) in 0:29. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/12 Ladytron - Whitelightgenerator.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 5DE87CEA     AccurateRip CRC: C4C552DC (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-12]
  AccurateRip Verified Confidence 4 [CRCv2 c4c552dc]
  AccurateRip Verified Confidence 6 [CRCv2 a8521168], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 566b48a7], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 c4c552dc]

Track 13:  Ripped LBA 210548 to 229144 (4:07) in 0:29. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/13 Ladytron - All the Way.m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 2BA64C1B     AccurateRip CRC: D832389C (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-13]
  AccurateRip Verified Confidence 4 [CRCv2 d832389c]
  AccurateRip Verified Confidence 6 [CRCv2 cff2107d], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 65765159], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 d832389c]

Track 14:  Ripped LBA 229144 to 257227 (6:14) in 0:43. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/14 Ladytron - Sugar [Archigram Remix].m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 82F2A9D3     AccurateRip CRC: 86A93103 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-14]
  AccurateRip Verified Confidence 4 [CRCv2 86a93103]
  AccurateRip Verified Confidence 6 [CRCv2 66cd9ed5], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 425b0c14], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 86a93103]

Track 15:  Ripped LBA 257227 to 281260 (5:20) in 0:35. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/15 Ladytron - International Dateline [Simian Mobile Disco Remix].m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: 78A1E826     AccurateRip CRC: BA5152B1 (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-15]
  AccurateRip Verified Confidence 4 [CRCv2 ba5152b1]
  AccurateRip Verified Confidence 6 [CRCv2 847cd57a], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 31406910], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 ba5152b1]

Track 16:  Ripped LBA 281260 to 311935 (6:49) in 0:43. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/16 Ladytron - Destroy Everything You Touch [Hot Chip Remix].m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: F1099246     AccurateRip CRC: 98977F5E (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-16]
  AccurateRip Verified Confidence 4 [CRCv2 98977f5e]
  AccurateRip Verified Confidence 6 [CRCv2 9dffbd56], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 16758d8e], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 98977f5e]

Track 17:  Ripped LBA 311935 to 342355 (6:45) in 0:41. Filename: /Users/Ryan/Music/iTunes/iTunes Media/Automatically Add to iTunes.localized/Ladytron/Witching Hour/17 Ladytron - Soft Power [Vicarious Bliss Gutter Remix].m4a
  AccurateRip: Accurate (confidence 4)     [Pass 1]
  CRC32: DF5F36BE     AccurateRip CRC: 591687DA (CRCv2)     [DiscID: 017-002b398a-0224b68c-0011d411-17]
  AccurateRip Verified Confidence 4 [CRCv2 591687da]
  AccurateRip Verified Confidence 6 [CRCv2 55067615], Using Pressing Offset +6
  AccurateRip Verified Confidence 3 [CRCv1 f459a191], Using Pressing Offset +6
  AccurateRip Verified Confidence 4 [CRCv2 591687da]

--------------

[Spoon]

>slower speed than usual

It is the drive which decides the speed to use.

If AccurateRip verifies it will be 1 pass, if the data is such that it does not verify then a 2nd pass is needed, this is secure ripping in action, to get you the correct result.