MIDI notes shifted and/or lost when recording from anywhere but 0:00

Key:

| = start or end of region
o = note

If I record:

0:00
|       o   o     o |

My recorded region is, as expected:

0:00
|       o   o     o |

If I record:

0:05
|       o   o     o |

then, at best, the space between the region start and first note gets deleted:

0:05
|o   o     o | 

or worse, some notes disappear:

0:05
|   o |

or nothing records

0:05

Is this a known issue? I couldn’t find it in the bug tracker. Am I missing a setting somewhere that will fix this?