Blarf has been working for the past week on his kernel, now at v53. You might want to stick with this kerne since it is built specifically for the Optimus V. But, it doesn't take too long to flash a kernel, so why not try them both out?
I've read bug reports on every CM7 ROM for the OV about this, not sure what causes it at this time. I'm guessing a conflict with a CM7 setting, but that's pure speculation. Perhaps you could try grabbing a logcat and dmesg while setting a custom ringtone, and set a custom ringtone to a phone you have handy and call yourself. Then post the logcat/dmesg to pastebin, or just attach here if that's too much trouble.
[i didnt know how to run a logcat i had to look it up] D/alogcat ( 2633): stopping ...
D/alogcat ( 2633): starting ...
D/alogcat ( 2633): stopped
I/AudioService( 176): AudioFocus requestAudioFocus() from AudioFocus_For_Phone_Ring_And_Calls
I/HeadsetService( 611): During phone call: disable DSP.
D/AndroidRuntime( 611): Shutting down VM
W/dalvikvm( 611): threadid=1: thread exiting with uncaught exception (group=0x40018560)
D/AudioFlinger( 125): setParameters(): io 1, keyvalue routing=1, tid 171, calling tid 125
E/AudioHardwareMSM72XX( 125): doRouting CALLED, outputDevices = 0x1, mFmRadioEnabled = 0
I/AudioHardwareMSM72XX( 125): Routing audio to Handset
W/AudioHardwareMSM72XX( 125): Routing to 5 really (current: 0)
E/AudioHardwareMSM72XX( 125): Parsing error in AudioFilter.csv.
D/AccelerometerListener( 264): enable(false)
I/PROFILE ( 176): Group: Gmail containing : com.android.phone : false
I/PROFILE ( 176): Group: Phone containing : com.android.phone : true
V/AudioManager( 264): shouldVibrate, group: Phone mode: DEFAULT
I/PROFILE ( 176): Group: Gmail containing : com.android.phone : false
I/PROFILE ( 176): Group: Phone containing : com.android.phone : true
I/PROFILE ( 176): Group: Gmail containing : com.android.phone : false
I/PROFILE ( 176): Group: Phone containing : com.android.phone : true
V/AudioManager( 264): shouldVibrate, group: Phone mode: DEFAULT
D/AudioHardwareInterface( 125): setMode(RINGTONE)
D/AudioFlinger( 125): setParameters(): io 1, keyvalue routing=2, tid 171, calling tid 125
E/AudioHardwareMSM72XX( 125): doRouting CALLED, outputDevices = 0x2, mFmRadioEnabled = 0
I/AudioHardwareMSM72XX( 125): Routing audio to Speakerphone
W/AudioHardwareMSM72XX( 125): Routing to 0 really (current: -1)
V/NotificationService( 176): Active profile: Default
I/PROFILE ( 176): Group: Gmail containing : com.android.phone : false
I/PROFILE ( 176): Group: Phone containing : com.android.phone : true
V/NotificationService( 176): Pkg: com.android.phone group: Phone
E/AudioHardwareMSM72XX( 125): Parsing error in AudioFilter.csv.
E/AudioHardwareMSM72XX( 125): Parsing error in AudioFilter.csv.
W/AssetRedirectionManager( 176): No such resource found for com.upwardspiral.Blue_Bionic
drawable/com_android_phone_ic_in_call_touch_answer
W/AssetRedirectionManager( 176): No such resource found for com.android.phone:color/incall_incall_callTypeSip
V/alogcat ( 2633): save instance
V/alogcat ( 2633): paused
I/InCallScreen( 264): onCreate()... this = com.android.phone.InCallScreen@40552cc8
D/alogcat ( 2633): stopping ...
W/ResourceType( 264): getEntry failing because entryIndex 65 is beyond type entryCount 1
D/alogcat ( 2633): stopped
I/Process ( 611): Sending signal. PID: 611 SIG: 9
I/power ( 176): *** set_screen_state 1
I/ActivityManager( 176): Displayed com.android.phone/.InCallScreen: +1s876ms
I/PROFILE ( 176): Group: Gmail containing : com.android.phone : false
I/PROFILE ( 176): Group: Phone containing : com.android.phone : true
V/AudioManager( 264): shouldVibrate, group: Phone mode: DEFAULT
D/InCallTouchUi( 264): onDialTrigger(whichHandle = 3)...
D/InCallTouchUi( 264): updateState: Too soon after last action; not drawing!
D/InCallTouchUi( 264): updateState: Too soon after last action; not drawing!
I/AudioService( 176): AudioFocus abandonAudioFocus() from AudioFocus_For_Phone_Ring_And_Calls
D/AudioHardwareInterface( 125): setMode(NORMAL)
D/alogcat ( 2633): stopping ...
D/alogcat ( 2633): scheduling periodic saves
D/alogcat ( 2633): starting ...
V/NotificationService( 176): Active profile: Default
I/PROFILE ( 176): Group: Gmail containing : org.jtb.alogcat : false
I/PROFILE ( 176): Group: Phone containing : org.jtb.alogcat : false
I/PROFILE ( 176): Group: Calendar containing : org.jtb.alogcat : false
I/PROFILE ( 176): Group: Email containing : org.jtb.alogcat : false
I/PROFILE ( 176): Group: SMS containing : org.jtb.alogcat : false
V/ProfileManager( 176): No active group, returning default: Other
V/NotificationService( 176): Pkg: org.jtb.alogcat group: Other
V/alogcat ( 2633): started
V/alogcat ( 2633): resumed
W/asset ( 241): deep redirect failure from 0x01030068 => 0x0a060003, defStyleAttr=0x01010084, defStyleRes=0x01030022, style=0x00000000
W/asset ( 241): deep redirect failure from 0x01030067 => 0x0a060002, defStyleAttr=0x01010084, defStyleRes=0x01030022, style=0x00000000
W/asset ( 241): deep redirect failure from 0x01030067 => 0x0a060002, defStyleAttr=0x01010084, defStyleRes=0x01030022, style=0x00000000
D/AccelerometerListener( 264): enable(false)
V/NotificationService( 176): Active profile: Default
I/PROFILE ( 176): Group: Gmail containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Phone containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Calendar containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Email containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: SMS containing : com.bel.android.dspmanager : false
V/ProfileManager( 176): No active group, returning default: Other
V/NotificationService( 176): Pkg: com.bel.android.dspmanager group: Other
I/HeadsetService( 2680): Starting service.
I/Effect-Equalizer( 125): EQ_PARAM_NUM_BANDS OK
V/NotificationService( 176): Active profile: Default
I/PROFILE ( 176): Group: Gmail containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Phone containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Calendar containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: Email containing : com.bel.android.dspmanager : false
I/PROFILE ( 176): Group: SMS containing : com.bel.android.dspmanager : false
V/ProfileManager( 176): No active group, returning default: Other
V/NotificationService( 176): Pkg: com.bel.android.dspmanager group: Other
I/HeadsetService( 2680): Phone status idle: enable DSP.
I/Effect-BassBoost( 125): New strength: 0
I/Effect-Equalizer( 125): Setting band 2 to 0
I/Effect-Equalizer( 125): Setting band 2 to 1
I/Effect-Equalizer( 125): Setting band 2 to 2
I/Effect-Equalizer( 125): Setting band 2 to 3
I/Effect-Equalizer( 125): Setting band 2 to 4
I/Effect-Equalizer( 125): Setting loudness correction reference to 100.000000 dB
E/AudioHardwareMSM72XX( 125): Parsing error in AudioFilter.csv.
D/Email ( 770): *** synchronizeMailboxGeneric ***
I/ActivityThread( 2690): Pub com.facebook.katana.provider.LoggingProvider: com.facebook.katana.provider.LoggingProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.NotificationsProvider: com.facebook.katana.provider.NotificationsProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.KeyValueProvider: com.facebook.katana.provider.KeyValueProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.ChatHistoryProvider: com.facebook.katana.provider.ChatHistoryProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.CacheProvider: com.facebook.katana.provider.CacheProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.UserValuesProvider: com.facebook.katana.provider.UserValuesProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.PagesProvider: com.facebook.katana.provider.PagesProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.MailboxProvider: com.facebook.katana.provider.MailboxProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.UserStatusesProvider: com.facebook.katana.provider.UserStatusesProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.PhotosProvider: com.facebook.katana.provider.PhotosProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.EventsProvider: com.facebook.katana.provider.EventsProvider
I/ActivityThread( 2690): Pub com.facebook.katana.provider.ConnectionsProvider: com.facebook.katana.provider.ConnectionsProvider
I/dalvikvm( 2690): Jit: resizing JitTable from 512 to 1024
D/alogcat ( 2633): saving log to: /sdcard/alogcat/alogcat.2011-07-24-00-15-30-0700.txt
D/dalvikvm( 2690): GREF has increased to 201
D/Cache ( 2091): Opened database
D/Cache ( 2091): Closed database
I/dalvikvm( 2633): Jit: resizing JitTable from 1024 to 2048
D/Cache ( 2091): Opened database
D/Cache ( 2091): Closed database
. this is my first one so heres my first try.