Logged Voucher Redistribution

 We have an occassional problem with the Voucher JE Redistribution.

We use voucher logging to pay credit card accounts.  Then when expense reports are received, the redistribution is used to properly expense the amounts.  The logging works fine, credits A/P and debits an A/R account. The redistribution debits the expense accounts and credits the A/R account.  About 1 in 50 of these redistributions creates 2 credits to the A/R account and therefore an unbalanced JE.  Have to use SQL to delete the duplicate line. 

What could be causing this duplicate line?  Does not happen all the time and cannot replicate it in test environment.