DDJ-RX audio glitches with rekordbox

Good evening, 

I'm quite dissappointed. I've bought my DDJ-RX a week ago.

After having some issues with the USB cable thats inside (my laptop didn't recognize the unit), I tried a no name USB cable and it worked instantly. 

After a while playing around I've noticed some serious audio glitches, even dropouts and serious lags. I did some research, but it wont getting better. 

To describe the problem: 

When I start rekordbox everything seems to be ok. The "Audio Dropout Meter" is somewhere at 25%. Then I start a track and still there is everything smooth, but when I activate the "FX Panel" above the "Needle Search" the Audio Dropout Meter" peaks near to 90% and sticks around the area. Turning off the "FX Panel" doesn't help at all and the audio glitches are getting worse. 

In standby the rekordbox software consumes around 20% of my CPU, when using my unit it's around 70-80% and after I turned on the "FX Panel" it's peaking to the limit.

I'm running rekordbox version 4.2.5 on an acer laptop with the following specifications:

OS: Windows 10 Home 64-Bit

Processor: Intel Core i5-4200 CPU @ 1.60 GHz 2.3 GHz 

RAM: 8.00 GB 

Troubleshooting I've done so far:

- Another USB Cable. After I changed the USB Cable my laptop recognized the unit and it worked, also with the cable, wich was inside the box. The issues are still the same.

- I've set the "Waveform Drawing Rate" on "Low Speed" and set the "Buffer Size" to "2048 Samples (42.7 ms)". It helped a bit, the massive audio dropouts and software lags were decreased and the "Audio Dropout Meter" isn't anymore above 75%. Anyway there are some minor audio glitches, but still noticeable and very annoying. 

- I've tried the whole unit and software on another laptop, with slightly poorer specifications and Win 7 running. Same problems. 

- I've also searched in the forums for solutions, but just found something like the first or second. 

- Also tried the unit with VDJ 8 and Traktor Pro 2. There were no issues like that, I would use these programs instead, but since the DDJ RX was designed for rekordbox, I can't have all features. 

I'm disappointed and I slowly get angry since I paid a thousand bucks for this unit and I can't enjoy the sound of it. 

Sorry for my bad english, but I really need help.