Windows -> samba - slow write speed

I have a Debian linux machine with samba Version 4.13.13-Debian on a peer-to-peer network. I've just run a LAN speed test, and it gives a considerably slower write speed from Windows -> Debian, than Windows -> Windows. Here are the stats:

Win -> Samba: Write 439.0 Mbps, Read 684.0 Mbps
Win -> Win: Write 758.5 Mbps, Read 655.9 Mbps

Here is the [globals] section of smb.conf

[global]
panic action = /usr/share/samba/panic-action %d
workgroup = WORKGROUP
server string = %h server (Samba %v)
passdb backend = tdbsam
obey pam restrictions = Yes
passwd program = /usr/bin/passwd %u
passwd chat = *Enter\snew\sUNIX\spassword:* %n\n *Retype\snew\sUNIX\spassword:* %n\n .
log file = /var/log/samba/log.%m
max log size = 1000
socket options = TCP_NODELAY
dns proxy = No
invalid users = root
printing = cups
printcap name = cups
time server = yes
dos filetimes = yes
fake directory create times = yes
dos filetime resolution = yes
delete readonly = yes
log level = 1
read raw = yes
write raw = yes

I'd welcome any suggestions

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