[GNC] Odd Invoice Total (Rounding Issue Maybe)

[Jeff]

Hi Group.
I am just doing some testing testing with updated versions (to me) of 
GnuCash.

I have been using GnuCash for a while on an older machine, it is running 
2.6.17 and it is working perfectly, unfortunately the machine it is on 
is starting to have issues, so am in the process of migrating to a newer 
machine, and therefore a newer version of GnuCash (finally).

The issue I'm having is on a specific Invoice the TOTAL shown down the 
bottom is 1 cent out.  I could understand it if I was doing % discounts 
etc, but the invoice is very basic, and the total seems to be correct, 
until the last entry.

Invoice Details:
Date      Description      Action     Quantity     Unit Price Discount 
Type  Discount How  Discount   Tax Subtotal   Tax
Today    Item 1               Material       1 $1049.00       % 
<                                        X     $953.64    $95.36
Today    Item 2               Material       1 $222.00       % 
<                                        X     $201.82    $20.18
Today    Item 3               Material       1 $15.00       % 
<                                        X       $13.64 $1.36
Today    Item 4               Material       1 $30.00       % 
<                                        X       $27.27 $2.73
Today    Item 5               Material       1 $59.15       % 
<                                        X       $53.77 $5.38
Today    Item 6               Project         1 $200.00       % 
<                                        X     $181.82     $18.18

The Discount Type and Discount How, are just the prepopulated values and 
are not used as there is no Discount amount.

The TOTAL at the bottom left of the Invoice entry screen is correct 
until adding the last entry, where it then shows:  $1,575.16 instead of 
the expected $1,575.15.

I have tried adding in the Invoice details to a new Invoice, and using 
two different versions of GnuCash, both seem to show the same 
behaviour.  Are there any suggestions as to why this may be happening, 
and how to fix it?  It is not very comforting that what appears to be a 
simple Invoice, with not discounts etc, is added up wrong.  If I change 
the Item 5 entry to $59.14 I correctly get $1,575.14.  But once again 
changing the Item 5 to $59.15 gives a Total of $1,575.16.

Tested on
OS                          GnuCash
Kubuntu 21.10    3.8, Build ID: 3.8b+(2019-12-29)   Finance::Quote: 
1.49        Installed via Package Manager
Kubuntu 22.04    4.8, Build ID: 4.8a+(2021-09-28)   Finance::Quote: 
1.51        Installed via Package Manager

Thanks in advance for any suggestions.
Regards,
Jeff.