Bruteforce not finding simple 4 letter hash?

[mho]

I see this is an old post.
But I have the same problem, was it ever looked at?
I am running under Windows 11 with Hashcat 6.2.6 and Intel Arc a750, running with new drivers. 

Hashcat has trouble finding hashes with the optimized kernel

"87654321"
.\hashcat --potfile-disable -m 1000 -O -a 3  D109D4B749ABA95D12042DCDBD8ADD2D ?d?d?d?d?d?d?d?d

If I remove the -O flag it is found.
This is bad. I work as a pentester an I am dependent that I get accurate results.
I have run hashcat for many days with the -O flag


Session..........: hashcat
Status...........: Exhausted
Hash.Mode........: 1000 (NTLM)
Hash.Target......: d109d4b749aba95d12042dcdbd8add2d
Time.Started.....: Sat Dec 14 20:54:31 2024 (0 secs)
Time.Estimated...: Sat Dec 14 20:54:31 2024 (0 secs)
Kernel.Feature...: Optimized Kernel
Guess.Mask.......: ?d?d?d?d?d?d?d?d [8]
Guess.Queue......: 1/1 (100.00%)
Speed.#1.........:  568.2 MH/s (1.78ms) @ Accel:128 Loops:100 Thr:32 Vec:4
Recovered........: 0/1 (0.00%) Digests (total), 0/1 (0.00%) Digests (new)
Progress.........: 100000000/100000000 (100.00%)
Rejected.........: 0/100000000 (0.00%)
Restore.Point....: 1000000/1000000 (100.00%)
Restore.Sub.#1...: Salt:0 Amplifier:0-100 Iteration:0-100
Candidate.Engine.: Device Generator
Candidates.#1....: 10524799 -> 69699999