Kunick Leisure claims it is under pressure because of a decline in the number of pub-goers and keeping up with major pub deals.
The amusement machine supplier said it was fighting to maintain margins despite the challenge of "continued lower footfall in pubs".
And it added that its cost levels and margins were being affected by the large numbers of pubs changing hands.
"The costs of the changeover process are not easily compensated for in the short term," the company said.
Kunick Leisure is meeting this challenge by developing new games and investing in hi-tech systems for administration and finance.
It has now installed 3,500 of its new GamesNet machines, which are internet-based terminals offering different down-loadable games.
Kunick Leisure increased operating profit for the six months to March 31 by 17 per cent to £5.2m and turnover by one per cent to £48.7m
This helped the whole of the Kunick group, which also manages fitness clubs, to more than double its half-year pre-tax profits to £6.38m. Turnover in its continuing businesses was up 13 per cent to £84m.
This followed improvements in its troubled Leisure Connection business, which specialises in running fitness centres within local authority leisure centres.
Problems with integrating the business led to two profits warnings last September, but group chief executive Colin Daniels said it had won new contracts and was showing "positive results".