Spurs have suffered back-to-back 3-0 defeats, with Sunday's performance against Chelsea drawing more frustration.
Kane missed the opening two games of the season, both matches the club won, before he returned against Wolves on August 22.
Nuno Espirito Santo's side won on that occasion too, but they have been far from their best with the striker back.
The 27-year-old has failed to score a Premier League goal this season having asked the club to leave this summer.
Man City reportedly made a bid for him, but Spurs were said to be demanding a fee of around £150million.
The transfer saga resulted in Kane staying, but there are clearly problems still there.
Tottenham legend Clive Allen told talkSPORT he thought the striker was still affected by what happened in the summer, while Roy Keane ripped into his performance on Sky Sports.
Former Spurs midfielder, O'Hara, added his reaction to Sunday's dismal display on the talkSPORT Breakfast on Monday morning, and admitted Spurs looked better without Kane in the team.
"It's tough one for me as Harry Kane is Mr Tottenham, in my opinion, but I look at his body language and look at the way he's playing and he's not playing very well," he said.
"I kind of enjoyed Spurs at the beginning of the season when he didn't play. I know that sounds bad because he is a great player and he is someone who you need in your team, but he's come back into the team and we can't win.
"When it was [Steven] Bergwijn, [Lucas] Moura and [Heung-min] Son up front, we sat in, we were composed, we soaked up the pressure and tried to hit teams on the counter attack.
"Harry Kane has come back and he's trying to do everything. For some parts of the game he's playing as a holding midfielder!
"They are doing too much, we need you to play up front and where things can happen.
"I feel like he's slowing things down for us a little bit at the minute.
" You can't criticise him for what he is and what he's done for the football club, but at the moment he's not playing very well for us."
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