the problem: the keys, drum pad, and pitch shifter work fine, but none of the knobs and sliders seem to be sending midi. on the keyboard display, it shows that they are active/working, but in fl studio, no midi comes through when they are moved. this problem just recently came up; before this, the keyboard worked fine. i took the keyboard to the music shop in which i bought it, and they tried using a different midi keyboard to see if the problem persisted. it didn't; the other keyboard worked 100%, so we concluded that the issue is with the a-800 pro. 
 
things i've tried: i have done a factory reset; i have installed the latest driver and smf update; i have tried restarting my computer and the keyboard. so far, nothing has worked. 
 
ideas? 

Hi, I don't use FL Studio but let me ask you this first.
Which of the control maps (1-19) in the A-800Pro are you using?

it was on the default setting, 1. 

Ok, I'm not at home so I can't check what messages are assigned to the pads, sliders, etc. in map #1, but could you try this? :

Launch A-Pro Editor, select channel 1 in the editor and click Receive.
Once the editor received the data of map #1 from the A-Pro hardware, double click the pad 1 to check which port it uses. Then double click slider 1 and check the port. Are the ports same?

Ok, I got home and checked the Map #1 Cubase SOLO map. (My explanation above was a bit wrong. It's "Control Map 1" instead of "channel 1," and you don't need to double-click. It's single-click.)
 
The reason why the drum pads work and play the drums is because they are programmed to send Note messages, and the reason why sliders and knobs don't work is because they are programmed to send strange messages that I don't understand. 
Since this map is designed for use with Cubase, I recommend creating a new map for FL Studio.
 
Actually, I have a map that I created for use with Studio One (not particularly for this daw, so I named it "Non-SONAR Map") and it may work well with FL Studio as well. This map is based on SONAR ACT MAP2 (which Sonar automatically sends to A-Pro when it's launched) and pads, buttons, knobs and sliders are ALL programmed to transmit the standard Control Change messages. So if you want to control parameters in FL Studio using A-Pro's pads, buttons, knobs and sliders, this map will do the job. If you want to use the drum pads as drums, then you need to assign the same message that Cubase SOLO map uses to these pads.
 
I've uploaded the map here so you can download and try it (downloadable for 1 week only):
https://box.raksul.com/dl...1bc107a7ce1376e53e286e
 
Hope that helps

yes, both are using port 2. 

ok, i have figured out a solution after talking with a Roland tech representative over the phone. somehow, the controls maps got erased, and none of them were programmed to utilize any of the sliders or knobs. i went on to a-pro editor and reactivated each knob and slider on control map 1, transmitted this data to the a-pro, and now the sliders/knobs are sending midi. 
 
thanks for your input Jlien X
 

Glad to hear the problem is sorted out. But it's strange, because the factory reset normally resets everything, including the control maps. I wonder what happened...