Switching banks and credit rating

Hi there,

I'm new to the forum so please be gentle and bear with me.

I switched to Santander in January 2015 after banking with Barclays for about 12 years with no benefits. Then Santander increased their 123 account fees so closed my credit card account and switched my current account to Halifax in October 2015 since I already had my mortgage with them so I thought it would be better. However, I have found their service appalling over the last 3 months and considering moving to First Direct but concerned that this wouldn't look good on my credit file and may affect my rating. Any advice on whether to switch or stick it out with Halifax would be much appreciated.

Thanks in advance.