Does Karma decide the interest and success in our chanting?

 Does Karma decide the interest and success in our chanting?

Good karma gives good next birth. But, continuance of that life and performing new good or bad activities depend on his free will.

However, whether he will continue as a devotee even in this issue-free family, or, he falls victim of the comforts, depends on how he uses his free will given by Krishna.

Karma network just gives a birth in a good family again to facilitate him to follow devotion.  If he uses the comfortable new life to practice devotion without issue-barriers, he will be given a chance to go back to Krishna.  Or, if he misuses his free will and involve in materialistic comforts, then, he will be given the next birth according to his present deeds.

However, since, Krishna is so powerful,  He will not allow the devotee’s devotion go waste.  
Therefore, he will give him a suitable birth that will MAKE HIM follow devotion sincerely.  If the devotee does not utilize this opportunity, Krishna allows him many births and he will come to serious devotion one day.

Whether he goes to higher planets and again comes to earth, or, he directly takes birth on earth again depends on how much he was involved in devotion in his previous birth.

Let us read what Krishna says in Bhagavad Gita (6-41): 

“The unsuccessful yogi, after many, many years of enjoyment on the planets of the pious living entities, is born into a family of righteous people, or into a family of rich aristocracy.”

Even while taking birth, that child would have been destined that it will choose a devotional way of life.

Now, in your case, you have taken birth in a suitable family as per your previous karma.  Now, you are following chanting.   Maya is trying her level best to pull you back to materialistic way of life because it is her duty.

Unless you dedicate your mind fully in following devotional practices, you can not drive maya out.
If our devotion is sincere, maya can not divert us.

Therefore, consider that you are fortunate to have started chanting the Lord’s Names.  Lord does not interfere in our free will.  However, he eagerly expects us to come to Him.

Now, you have to decide whether to honour the call by Krishna and go back to Him and lead an eternal way of blissful Service in the kingdom of Krishna. OR whether to honour the call by maya and take birth again and again in this painful material world with some temporary pleasures.

If you decide in favour of case 1, then, give dedication to chanting.

If you are dedicated and chant with the taste, you will not be diverted from chanting by maya.