Provide the theme summaries for the following conversation: 

#Person1#: We have some quality-control problems. Mr. Zhang. We need to go to the source to work them out.
#Person2#: What problems are you having exactly?
#Person1#: The complaint rate for our new product line is very high, almost eight percent.
#Person2#: That is high.
#Person1#: Yes. We keep finding problems when testing the sound boards.
#Person2#: But your promotional materials claim the broads are the least expensive of their types on the market.
#Person1#: The least expensive, but still fully functional. And we think that your factory needs to take measures to improve quality-control.
#Person2#: That will involve additional expenses for us, which we will have to pass on to you as a rate hike.
#Person1#: I am afraid that is not acceptable. Your contract says that you will deliver a product with a reject rate of less than six percent.
#Person2#: Well. I will tell you what, Mr. Li. I will review the contract and talk with management. Then we will get together and hash this out.

Summary: 
Mr. Li reports the high complaint rate of the new product line to Mr. Zhang and urges him to improve quality-control. Mr. Zhang demands a rate hike but is turned down by Mr. Li according to the signed contract.