GTX 670 Issues with oclHashcat-plus

[th3l0b3]

i have the same card. I am running this in Windows but for some reason, cannot get more than 15k in speed for WPA/WPA2. any way i can boost this up a bit?

C:\Users\lcobb\Desktop\HashCat>cudaHashcat-plus64.exe -m 2500 -a 3 --gpu-devices
1 ZombieNet01.hccap -1 ?u?l?d ?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1
cudaHashcat-plus v0.08 by atom starting...

Hashes: 1
Unique salts: 1
Unique digests: 1
Bitmaps: 8 bits, 256 entries, 0x000000ff mask, 1024 bytes
GPU-Loops: 64
GPU-Accel: 1
Password lengths range: 8 - 15
Platform: NVidia compatible platform found
Watchdog: Temperature limit set to 90c
Device #1: GeForce GTX 670, 2048MB, 705Mhz, 7MCU
Device #2: skipped by user
Device #1: Allocating 1MB host-memory
Device #1: Kernel ./kernels/4318/m2500.sm_30.64.cubin

Status.......: Running
Input.Mode...: Mask (?1?1?1?1?1?1?1?1?1?1?1?1?1?1?1)
Hash.Target..: ZombieNet (XX:XX:XX:XX:XX:XX <-> XX:XX:XX:XX:XX:XX)
Hash.Type....: WPA/WPA2
Time.Running.: 15 secs
Time.Left....: > 10 Years
Time.Util....: 15079.8ms/4.0ms Real/CPU, 0.0% idle
Speed........: 15567 c/s Real, 15552 c/s GPU
Recovered....: 0/1 Digests, 0/1 Salts
Progress.....: 234752/4177248169415651 (0.00%)
Rejected.....: 0/234752 (0.00%)
HW.Monitor.#1: 96% GPU, 55c Temp

Any help to get me boosted up to faster speeds on this? I mean i figured with over 1000 CUDA cores, i would be going about 50k at least