Because the IP Profile makes an allowance for overheads, any lines which have Interleave High or G.INP High Retransmission DLM Profiles will find the additional redundancy increases the total overhead allowance to circa 8-9%.
Your IP profile isn't stuck. It is what it should be.You are on a Huawei cabinet and your line has a 3dB snrm target. This usually means the line is set to Retransmission High which gives between 91-92% IP profile.Your IP profile is 91.6% of the sync speed.http://www.kitz.co.uk/adsl/IPprofile.htm#FTTC_ipProfile