Manage Groups paging faulty - showing wrong amount of contacts

If you go to a group in manage groups you can see less people that you should per page.

To reproduce:

Remove & add the first contact in a group several times. Group should have more than 25 contacts in it

Browse to that group from manage groups - set the pager to 25 & count the number of contacts on the first page - will be less than 25

EXTRA INFO
Query run looks like this

the group_contact_id second to last is the problem as it returns a record for when the contact was added & another from when they were deleted

SELECT DISTINCT(contact_a.id) as contact_id, contact_a.contact_type as `contact_type`, contact_a.contact_sub_type as `contact_sub_type`, contact_a.sort_name as `sort_name`, contact_a.display_name as `display_name`, contact_a.do_not_email as `do_not_email`, contact_a.do_not_phone as `do_not_phone`, contact_a.do_not_mail as `do_not_mail`, contact_a.do_not_sms as `do_not_sms`, contact_a.do_not_trade as `do_not_trade`, contact_a.is_opt_out as `is_opt_out`, contact_a.legal_identifier as `legal_identifier`, contact_a.external_identifier as `external_identifier`, contact_a.nick_name as `nick_name`, contact_a.legal_name as `legal_name`, contact_a.image_URL as `image_URL`, contact_a.preferred_mail_format as `preferred_mail_format`, contact_a.first_name as `first_name`, contact_a.middle_name as `middle_name`, contact_a.last_name as `last_name`, contact_a.job_title as `job_title`, contact_a.birth_date as `birth_date`, contact_a.is_deceased as `is_deceased`, contact_a.deceased_date as `deceased_date`, contact_a.household_name as `household_name`, IF ( contact_a.contact_type = 'Individual', NULL, contact_a.organization_name ) as organization_name, contact_a.sic_code as `sic_code`, gender.value as gender_id, gender.label as gender, individual_prefix.value as individual_prefix_id, individual_prefix.label as individual_prefix, individual_suffix.value as individual_suffix_id, individual_suffix.label as individual_suffix, IF ( contact_a.contact_type = 'Individual', contact_a.organization_name, NULL ) as current_employer, civicrm_address.id as address_id, civicrm_address.street_address as `street_address`, civicrm_address.supplemental_address_1 as `supplemental_address_1`, civicrm_address.supplemental_address_2 as `supplemental_address_2`, civicrm_address.city as `city`, civicrm_address.postal_code_suffix as `postal_code_suffix`, civicrm_address.postal_code as `postal_code`, civicrm_address.geo_code_1 as `geo_code_1`, civicrm_address.geo_code_2 as `geo_code_2`, civicrm_state_province.id as state_province_id, civicrm_state_province.abbreviation as `state_province`, civicrm_state_province.name as state_province_name, civicrm_country.id as country_id, civicrm_country.name as `country`, civicrm_phone.id as phone_id, civicrm_phone.phone_type_id as phone_type_id, civicrm_phone.phone as `phone`, civicrm_email.id as email_id, civicrm_email.email as `email`, civicrm_email.on_hold as `on_hold`, civicrm_im.id as im_id, civicrm_im.provider_id as provider_id, civicrm_im.name as `im`, civicrm_worldregion.id as worldregion_id, civicrm_worldregion.name as `world_region`, `civicrm_group_contact-22`.id as group_contact_id, `civicrm_group_contact-22`.status as status FROM civicrm_contact contact_a LEFT JOIN civicrm_address ON ( contact_a.id = civicrm_address.contact_id AND civicrm_address.is_primary = 1 ) LEFT JOIN civicrm_state_province ON civicrm_address.state_province_id = civicrm_state_province.id LEFT JOIN civicrm_country ON civicrm_address.country_id = civicrm_country.id LEFT JOIN civicrm_email ON (contact_a.id = civicrm_email.contact_id AND civicrm_email.is_primary = 1) LEFT JOIN civicrm_phone ON (contact_a.id = civicrm_phone.contact_id AND civicrm_phone.is_primary = 1) LEFT JOIN civicrm_im ON (contact_a.id = civicrm_im.contact_id AND civicrm_im.is_primary = 1) LEFT JOIN civicrm_worldregion ON civicrm_country.region_id = civicrm_worldregion.id LEFT JOIN civicrm_group_contact `civicrm_group_contact-22` ON contact_a.id = `civicrm_group_contact-22`.contact_id LEFT JOIN civicrm_group_contact_cache `civicrm_group_contact_cache_22` ON contact_a.id = `civicrm_group_contact_cache_22`.contact_id LEFT JOIN civicrm_option_group option_group_gender ON (option_group_gender.name = 'gender') LEFT JOIN civicrm_option_value gender ON (contact_a.gender_id = gender.value AND option_group_gender.id = gender.option_group_id) LEFT JOIN civicrm_option_group option_group_prefix ON (option_group_prefix.name = 'individual_prefix') LEFT JOIN civicrm_option_value individual_prefix ON (contact_a.prefix_id = individual_prefix.value AND option_group_prefix.id = individual_prefix.option_group_id ) LEFT JOIN civicrm_option_group option_group_suffix ON (option_group_suffix.name = 'individual_suffix') LEFT JOIN civicrm_option_value individual_suffix ON (contact_a.suffix_id = individual_suffix.value AND option_group_suffix.id = individual_suffix.option_group_id ) WHERE ( ( ( `civicrm_group_contact-22`.group_id IN ( 22 ) AND `civicrm_group_contact-22`.status IN ("Added") ) OR ( `civicrm_group_contact_cache_22`.group_id = 22 ) ) ) AND (contact_a.is_deleted = 0) ORDER BY contact_a.sort_name asc LIMIT 0, 50