Any updates on this? I have the same problems as @DocVooDoo and others, i.e. Adafruit code works like a charm, dht_var not.
Difference I noticed is that dht_var uses wiringpi library and Adafruit not?! I tried a reinstall of wiringpi package without success.
Next, I compared the implementations of dht_var and the Adafruit driver for DHT22.
The essence of the Adafruit code is in file Adafruit_Python_DHT/source/Raspberry_Pi_2/pi_2_dht_read.c. It is meant for Pi2 and Pi3, implemented in C, and defines a function int pi_2_dht_read(int type, int pin, float* humidity, float* temperature). It implements the communication with the sensor using a 1-wire bus. The rest of the Adafruit package is mostly (well-done) sugar-coating for Python usage and selecting the right driver for any given platform.
We could simply rewrite dht_var by using this driver code. What do you think?