@LCasper @Breeeze 

Have you tried using a Refund Receipt (New > Refund Receipt) to record the bounced check?  That creates an entry on the donor's account, removes the funds from your bank account so you can reconcile, and reduces the income based on the product/service selected on the refund receipt.  If you use the same product/service that was used on the invoice/sales receipt when you received the donation, the refund receipt will reverse the entry made at the time of the donation.